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DIALLING TONE

MALE:Police. What's your emergency?

MALE:Halt! Police officers!

Elite police units, created to crack the toughest of cases.

My role is investigating serious and organised crime.

This was out of the ordinary

and this was a high pressure situation.

Calm yourself down!

Their task? Tackle the villains...

You're wanted on suspicion of murder, all right?

..and bring them to justice.

A real "Who did it?"

With unique access to some of Britain's most talented detectives,

we explore, for the first time, their investigations...

We've spent years putting together

all of these tiny pieces of evidence.

..their methods...

The most bizarre investigation I've been involved in.

..and the evidence

that's put some of the UK's most dangerous criminals behind bars.

They are clever, and they're dangerous.

GUNSHOTS

The M62, one of Britain's busiest motorways.

A 31-tonne truck suddenly spins out of control.

TYRES SQUEAL

One man is left dead.

Another is mortally injured.

When someone is pronounced dead at the scene, it's horrible.

You can feel the air change around you.

You can feel the atmosphere.

Is this simply human error...

The driver's denied that there's been any faults.

..or does the rot go much deeper?

There was a sense that the driver was intimidated by the boss.

And how easy will that be to prove?

You've just got to take time

to gather all the evidence that you need.

In 2022, there were a staggering 333,000 road traffic accidents

across Great Britain.

Every 16 minutes, someone is killed or seriously injured.

Some RTAs are heartbreaking accidents,

while others can be the result of a serious criminal act,

and it's the job of the road traffic investigators

to dig deep to find the cause and the culprit.

My name is Ben Pearson,

and I'm a retired West Yorkshire police officer,

and I spent 19 years in the Roads Policing Unit.

The worst bit about being a police officer

is dealing with fatal collisions, dealing with dead bodies

and having to knock on people's doors and letting loved ones know

that their family member's never coming home again.

On April 3rd, 2018, at 9.30am,

police are called to the scene of a horrific road traffic collision.

A massive 31-tonne heavy goods lorry transporting a mobile home

has jack-knifed across the M62 central reservation.

When you're attending scenes

of a serious or fatal road traffic collision,

there's a lot going through your mind.

Is there anybody injured?

Is the scene safe?

And is the offender still at the scene, or have they made off?

The crashed vehicle had been at the start of a 600-mile round trip

from Hull, travelling in convoy with two other vehicles.

They were only 31 miles into the journey.

Was this an unavoidable accident or the result of a criminal act?

It was transporting mobile homes.

It was on an abnormal load escort,

and there was a slow-moving vehicle in front.

You're driving a big truck on a road.

It's a dangerous vehicle.

Tragically, the truck hits a car

travelling on the opposite carriageway.

When officers arrive at the scene, it's clear from the carnage

one of the two passengers is dead from the impact.

When someone is pronounced dead at the scene, it's horrible.

You can feel the air change around you. You can feel the atmosphere.

Everything just becomes different and sombre.

Officers discover the fatality is a 41-year-old married father of two.

We start thinking about the families that have got to be told

that a loved one's never coming home.

A 37-year-old male in the passenger seat is fighting for his life,

having sustained serious injuries.

First responders from the air ambulance are scrambled

to take him to hospital.

We aim to be at scene within 20 minutes

of a call coming in anywhere within Yorkshire.

I'm Stew Ashburner-McManus,

I am a seconded HEMS aircrew paramedic

and I'm working here at Yorkshire Air Ambulance.

When we're in the air, we normally get an update

that will tell us the status of the patient,

the potential injuries, any potential hazards on scene.

As the miles-long traffic jam builds up,

officers at the scene have the dangerous task

of clearing a section for the incoming crew.

Our first view of it is normally as we're coming into land,

and we'll be able to see the kind of impact.

We can work out the deceleration forces and the kind of injuries

that we're potentially going to be dealing with when we arrive.

The hazards normally involve other vehicles, debris.

Is there oil? Is there fuel? You know, is there a fire hazard?

The aircraft can create a lot of downwash

that might damage property. It can blow people over.

These are all things we've got to consider on a motorway.

It brings a unique set of challenges.

With a target time of one hour from call to arriving at hospital,

the crew hit the ground running.

Going by road from this location,

you're probably looking 45-50 minutes.

Traffic officers now have the harrowing job of unpicking the scene

to find out what caused this fatal collision.

It's extremely difficult to protect a crime scene on a motorway.

You've got cars, trucks.

People get frustrated. People get angry.

It throws a spanner in the works in the investigation.

The importance of preserving the evidence is a real challenge.

You've got to look at a road traffic collision as a murder scene.

Every single bit of evidence,

tyre marks on the road where the collision's first taken place,

how the vehicles are situated.

Key witnesses, CCTV all need to be obtained.

It's clear from the crash site what has happened,

but now investigators need to find out how it happened, and why.

You know someone's fatally injured at the scene.

You know there's devastation everywhere,

and you know it's not going to be an easy case.

The badly shaken and injured driver of the lorry

is questioned at the scene, where he explains his wheels locked

just before he careered over the central reservation.

The officers, they'd done all the various checks on the driver -

driving licence, insurance. They'd have been breathalysed at the scene,

and then they'd have been arrested by death by dangerous driving.

The driver is then airlifted to hospital.

Then the crash site section of the motorway is closed for 19 hours

as specialist forensic units take charge and search for evidence.

The forensic work that takes place is everything from skid tests,

brake tests, all CCTV's recovered, and all witness statements as well.

So all that needs clearing, there and then.

It's a long and timely process.

The next day, after being discharged from hospital,

..the driver is brought in to the police station for questioning.

But his story seems to have changed.

The driver's denied that there's been any faults with the brakes,

but he has admitted that the vehicle has locked up at some point

but doesn't know why.

Suspicious, the motorway officers start to view hours and hours

of dashcam footage recorded in the cab...

..and by the driver's colleague who was travelling behind

in a similar vehicle, transporting another mobile home.

To get dashcam footage in an incident like this is invaluable.

It's your eyes and ears at the scene.

The footage revealed that there's obviously been a massive problem

with the brakes of the offending vehicle.

The driver is struggling to control the vehicle.

He's having several issues of not being able to brake in time.

And then commenting as well,

saying that there's an issue with the brakes...

..and then that'll lead straight up to the collision itself.

TYRES SQUEAL

To see that is damning evidence.

An image speaks a thousand words.

While the driver is being questioned,

police are in touch with DVSA, the Driver And Vehicle Standards Agency,

who have taken delivery of the crashed truck.

They look at it with a fine tooth comb,

with Collision Investigation Unit,

and find out if there's any faults on the vehicles,

or is there a reason why the vehicle's just not stopped?

Commercial haulage vehicles are subject

to strict operating standards.

If anything goes wrong, it can be deadly.

Operator's licences are issued by the Traffic Commissioner,

and they've got to be satisfied that the haulier

is a fit and proper person to have an operator's licence

and that they've got a good maintenance regime.

My name is Ben Southam.

I'm a senior specialist prosecutor

with the Special Crime Division in the CPS.

I've been in the CPS for nearly 26 years.

When the case first comes to the CPS,

it's for what's called pre-charge advice.

So they're coming to us saying, "Look, we need to discuss with you

"whether or not we've got enough evidence or whether we need

"further evidence before we can make the decision to charge."

The challenge for the CPS is to establish who's at fault...

..the driver or the haulage boss,

who is responsible for maintaining the vehicles.

Most of the evidence came from the dashcam footage

from the two lorries.

The fatal collision happened just as they were going

over the Ouse Bridge.

He was obviously trying to slow down,

but his brakes weren't working,

and that then caused the lorry and the trailer behind it to jack-knife.

TYRES SQUEAL

Early background checks reveal in 2015,

the boss received a serious warning when the brakes failed

on one of his vehicles approaching a roundabout.

It hit a car and caused serious injury to that driver.

Is this a pattern? HORN BLASTS

The CPS are keen to impose a far more serious charge.

When you look at a case like this,

you can't only just look at the driver,

you've also got to look at the vehicle,

where the vehicle has come from, the company itself.

It's not as open and shut as what people think it is.

You need to start looking close to home and what the boss is doing.

But looking into the boss and his business is not simple.

It's very much like a jigsaw puzzle,

putting various pieces of the evidence together,

and we had to decide ultimately

whether to charge the haulage boss individually.

The decision was much more difficult because the evidence

was very different.

12 days after the crash, the second victim, a 37-year-old man

who's engaged to be married, sadly dies from a serious head injury.

It is now a double death by dangerous driving.

They both worked in the fashion industry

and they were driving to meet clients.

They were just going about their normal business.

No-one deserves this to happen to them.

Humberside Police are investigating a fatal collision

between a heavy goods vehicle and a car

containing two men, driving to work.

The CPS had been brought in to work on the prosecution case.

There is key video evidence from an accompanying vehicle.

The dashcam footage from the second lorry

showed how the collision occurred,

but it also showed a number of other vehicles.

I remember there was a particular Mini that was trying to get past.

Luckily for the driver of that car, it accelerated to get past

just seconds before the collision occurred.

Had it not done that, then that Mini would've probably been wiped out

as the lorry went through the central reservation.

TYRES SQUEAL

Determined to see just how widespread the negligence is,

officers dig deeper and contact the DVSA,

who have been looking into the owners of the crashed truck.

The DVSA, they do provide quite a lot of evidence to the police

around previous occasions when they'd stopped his vehicles

and found faults, particularly with things like tyres and brakes.

They issued in the region of 70 prohibitions over a number of years

in relation to his vehicles.

The haulage boss who ran and owned the company

is red-flagged on the DVSA system.

The focus began to shift away from the driver to the haulage boss.

It was a little bit like pulling a piece of string.

As soon as they started digging into the haulage boss,

they begin to get a much clearer picture

of the type of person that he was

and the type of business that he was running.

They then became aware of the fact that the boss had been disqualified

having an operator's licence by the Traffic Commissioner.

That then put him centre-stage of the investigation.

So although the driver had responsibility on the day,

it was the way in which the boss ran his company

that was the key point that we were trying to prove.

Officers start the challenging task of trying to dig up evidence

of the haulage boss's systemic negligence,

proving that he was the one responsible

for the horrendous fatal crash.

The haulage boss,

he had an insurance policy for drivers over 25,

but, in fact, a lot of his drivers were under 25.

The driver in this case was 22,

and of course, the reason for that is the insurance policy

will be considerably cheaper,

but also, he employed younger drivers

who he could boss and bully, effectively.

And if ever they stood up to him,

he just threatened them with the sack.

It turns out that the 39-year-old haulage boss from Hull

also has previous convictions for making false tachograph records

to conceal driver-hour infringements.

In order to convict the boss,

the CPS collate intel and evidence

to unravel how his haulage business runs.

We needed to get the evidence of the way that he ran his operation.

So that included the fact

that he wasn't getting vehicles repaired properly.

He was looking to cut corners, save costs wherever he could do.

We were trying to get evidence

to demonstrate that everything that happened within his business

happened with his knowledge and consent.

It's clear his focus is on profit,

regardless of rules to keep us safe on the roads.

The haulage boss had been disqualified

by the Traffic Commissioner previously

from having an operator's licence,

so he was using something called ghosting.

The haulage boss were a bit of a shady character

cos he'd opened a ghost company up under another name.

He'd go to other businesses that had an operating certificate

and be saying, "Please put my trucks on your certificate."

He was effectively using other companies as a front

for his own company.

He also set up a company in his mother's name,

purported to employ the drivers as a driver agency,

when, in fact, that was just a complete sham.

The reality was that the drivers were working for him,

being paid by him and doing work for his company.

He knew what he were doing. He were doing things very illegally.

It's more difficult to build a successful case against the boss,

but without it, will there be justice?

I decided to charge the haulage boss with gross negligence manslaughter.

Which is very rare.

19 years in roads policing,

I've never heard of someone being prosecuted for such a crime.

And there were some other offences

of aiding and abetting, causing death whilst uninsured.

The evidence demonstrates that he was responsible

for all the key decisions about how the company was run.

We felt that he was the person that was responsible and culpable.

The manslaughter charge is because of serious concerns

around the haulage boss's disregard for health and safety.

It was profit over safety.

That was the key issue, that wherever he could cut corners,

he did, and it was all about making money for him.

The team hunt for as much evidence as possible

of the boss systematically ignoring health and safety.

The dashcam showed both lorries stopped at a truck stop...

..and you could hear them talking about what they described

as a "Friday defect."

And what that meant to them was that there was a known fault

with the vehicle, but faults weren't repaired until Friday

or the weekend, so that the haulage boss could keep his wagons

on the road, earning money during the week.

It was a very key piece of evidence,

because it demonstrated the haulage boss's attitude to road safety

and prioritised making money over the safety of the public.

Forensic examination of the truck

reveals the problem with the brakes would have cost a mere £200 to fix.

The Collision Investigation Unit and the Driver Vehicle Standards Agency

actually found that it was just a rubber washer that had perished,

so when they put the brakes on, it were a four-to-six-second delay

before the trailer unit started braking.

And then when he took his foot off the brakes,

it were four to six seconds before the tractor unit

had had its brakes either applied or not applied.

So then, as they're going over the Ouse bridge, he put the brakes on.

So the brakes on the lorry worked,

but the brakes on the trailer didn't,

and that's what caused the jack-knife.

TYRES SQUEAL

£200 could have saved two people's lives.

It's a simple fix, and it could have been done easily.

By October 2020, two years on, the court is open to hear pleas.

So, the driver pled guilty

to two counts of death by dangerous driving,

and the haulage company boss pleaded guilty

to a health and safety offence, but not guilty to everything else.

So he went to trial, but he didn't give evidence.

Sometimes you've just got to stand up

and take ownership of what you've done.

And him not doing that shows no respect for the people

that have been fatally injured or their families.

During the boss's trial, in June 2021,

his defence relies heavily on blaming others -

primarily his junior employee, the driver.

There was a sense that both the driver and the other employees

were intimidated by the boss.

The evidence painted a very clear picture

of the type of business that he ran.

Basically, you did as you were told, or you got out.

The boss of the haulage company made every excuse under the sun.

So, it was the driver's fault, or it was the other operators,

that in fact it was their vehicles, not his own vehicles.

The lorry that was involved in the collision

was using an operator's licence for another company.

He tried to say that it was in fact that company that was running

that lorry, when in fact the evidence clearly showed

it was fulfilling an order for his company, using one of his drivers.

So it was very clear that in fact, it was his lorry doing his work.

And we know that he'd been running his business this way for years.

So, as the judge described, this was an accident waiting to happen.

I think it's frankly amazing that nobody else was killed

in this collision.

June 25th.

The haulage boss is found guilty

of the unprecedented and most serious of charges.

The driver is sentenced to nine years,

reduced to six on a guilty plea,

and is disqualified from driving for five years after his release.

The jury convicted the haulage boss of gross negligence manslaughter

and aiding and abetting, causing death whilst uninsured.

He sentenced the haulage boss to 15 years' imprisonment,

which is one of the longest sentences

that we're aware of for a workplace manslaughter prosecution.

I think that's a fantastic result

for all our officers' hard work and dedication.

What cases like this demonstrate

is how complex these investigations are,

that it's very much like putting together a jigsaw,

and therefore you've just got to take time to gather

all the evidence that you need.

The severity of the sentence

reflects how the blatant, systematic failures

of the haulage boss led to two innocent men losing their lives.

The judge appeared to have a very clear view of the haulage boss,

and certainly when he was sentencing him, he used phrases like

"lawless operation" and described the haulage boss as being greedy.

The judge made a really good comment at the end of this case,

saying that although cuts were made in the business,

they weren't made for reasons such as,

"I needed to feed my family" or "I needed to make ends meet."

He did it just for greed.

So people like this need to be behind bars.

I think the haulage boss is still in denial about what happened.

He has unsuccessfully tried to appeal his conviction

and he still blames everybody else but himself.

Coming up, after receiving reports

of the online radicalisation of a teenager,

counter-terrorism policing battle to stop

a deadly Islamist-inspired killing spree.

Alone in a dark bedroom in Essex,

a teenage boy is slowly becoming self-radicalised.

This case was unusual.

It's very strange for us to find somebody that young,

and somebody who has converted to Islam

and mainly done it themselves, online.

Could his online obsession turn into a rampage of terror

on the streets of London?

The subject had changed his WhatsApp profile to a term

that said "Kill non-Muslims."

But with no laws broken, the pressure is on

for counter-terrorism police to apprehend a teenager

determined to wreak terror in the name of Allah.

He was clearly ascribing to a radical form of Islam

and was determined to be an Islamist terrorist.

Over the past year,

terror arrests have risen by nearly 50% in the UK...

..helped by a massive escalation in teenagers being held

for plotting extremist attacks.

The threat changed very significantly

into low-sophistication terrorist attacks

committed by an individual, usually self-initiated.

22nd of May, 2017.

British citizen Salman Abedi carried out

one of the UK's most deadly extremist attacks

by detonating a home-made bomb in the Manchester Arena,

resulting in 23 deaths.

Since 2017, counter-terrorism policing

has helped stop 39 serious terror plots in the UK...

..and when they identify a new threat, they have to act fast.

SIREN WAILS

Cases can come to our attention in a number of ways.

Often, that can be a report from a member of the public

who thinks that they've seen something concerning.

April 2022 -

a number of mosques from East London and Essex

call the anti-terrorist hotline,

reporting a white teenager who's interested in violent jihad.

I'm Philip Mills. I'm a detective superintendent for SO15,

which is London's counter-terrorism policing unit,

and I'm responsible for leading investigations.

So the initial reports were primarily just concerned about

some of the comments that he'd been making, and his behaviours,

which they thought were supporting of acts of terror

and supporting of potentially wanting to be a jihadi.

They wanted to make it clear to him that that wasn't their beliefs

and something they wanted to tolerate in their mosques.

In the certainty that the UK faces future deadly attacks,

counter-terrorism officers take reports like this very seriously.

So, the anti-terrorist hotline is a dedicated line

which is staffed 24 hours a day, seven days a week, 365 days a year.

My name is Dominic Murphy.

I am the commander of SO15,

the counter-terrorism command here at the Metropolitan Police.

I'm responsible for managing nearly 2,000 officers and staff

who are involved in specialist and generalist

counter-terrorism response that is fit

for the future threats we face here in the UK.

But protecting the public from a potential mastermind

behind a deadly terror attack, before it's happened,

is challenging work for the counter-terrorism officers.

We would do our own research to understand who that individual was,

whether it was somebody that was already known to us.

We were trying to understand as much about them as possible.

The subject was 18 years old at the time.

He had been out of mainstream education since year eight.

He'd been involved in some violent episodes previously at school.

After being expelled, his behaviour deteriorated.

He would get stoned and argue with his mother.

He then attended an educational unit in Basildon until he was 16.

He is somebody who had been working part-time but during the pandemic

had converted from Christianity to Islam.

The subject's mother had become concerned

about some of his comments, some of his behaviour,

also what he was doing when he was out of the house,

the things he was looking at online.

They discover that the teenager's name has been flagged up

as a potential victim of radicalisation previously.

He'd been recommended an intervention programme.

Prevent is something that we use in the UK whereby if we think

somebody is at risk of radicalisation,

we can refer them to support services

to help them not become radicalised.

It's important to remember that Prevent is voluntary.

So whilst we can refer people to Prevent,

they do not need to stay there.

Worryingly, the teenager refuses to engage with Prevent.

So, at that point, that helps us make a decision

in relation to what our next actions are going to be.

The counter-terrorism team need to act with speed and caution.

Once a suspect knows that they're on to them,

they may accelerate their plans to commit a terror attack.

Operation Checkroom is launched.

The counter-terrorism team needs to ascertain the risks

the teenager presents to the public.

So one of the things the subject's mother was concerned about

was some of the media that he'd been watching online.

In 2020, lockdown meant that life online became the norm.

Everybody was quite isolated and indoors a lot,

and there were some concerns around some of the videos

that he had been watching and how those had changed

his opinions and his beliefs.

Despite living at home, the teenager becomes detached from the family.

He purchases a prayer mat, Islamist books, starts to learn Arabic

and will only eat halal food.

He was clearly following a radical form of Islam,

but some of our younger subjects

don't necessarily assign one ideology to their radical thoughts.

They will consume vast amounts of extreme media online,

mostly really violent media that can be of any sort.

It doesn't necessarily need to be related to Islam

or terrorism in any way.

It can be violent school shootings from America

or lots of other material.

His online radical views start to spill over into the real world.

His dress had changed.

He started wearing more formal Islamic clothing.

He had started criticising his sisters

in relation to their behaviours and had started saying some comments

which they thought were supportive of terrorism.

DSU Philip Mills needs to gather enough evidence

in order to make the decision to use the arrest under the Terrorism Act,

so they can get the teenager off the streets

in case he's planning an imminent attack.

We have a very difficult balance to take between the threat they pose

and allowing them to be out in the public

and securing as much evidence as possible to ensure that

when we arrest them, we're disrupting them in the longer term.

But getting the timing wrong could have disastrous consequences.

The teenager has broken no laws, but his extremist sympathies

are becoming more apparent.

He had changed his status profile

to a picture of a terrorist called Mohammed Emwazi,

who had murdered and beheaded some British and US nationals

in Syria many years ago.

More commonly known as Jihadi John, this Islamic State militant

had grown up - and been radicalised - in London.

The subject had changed his profile to a term that said,

"Kill non-Muslims wherever you find them,"

and clearly that's a very strong indication of how radical

and potentially violent this individual was.

It's always difficult to quantify how extreme someone's beliefs are,

until you can start to speak to them

and get a bit of a better understanding of them,

but certainly his behaviour...

To hear from both his mother and from people

that are interacting with him in the mosque,

certainly really concerning for us,

which is what led us to think that we wanted to try and arrest him

and commence a full investigation as soon as possible.

DSU Mills needs to proceed with extreme caution.

Clearly, we have to do an awful lot of research on the house.

The last thing we want to do is put anyone else in the house at risk,

including any younger children

or anyone who's not involved in the plot.

18th of May 2022.

Counter-terrorism officers arrest a teenager under the Police And Criminal Evidence Act...

..but the pressure is on.

They can only hold him for 24 hours, so they need to act fast.

The subject initially gave a prepared statement

about his religious beliefs, stating that he wasn't a terrorist,

that he had Islamic views, but that he believed

that they were acceptable views.

After that, he answered "No comment" to all the questions

that my investigators asked him.

So, very few terrorists talk to us in interview.

They may have really strong reasons

why they were doing a certain type of activity, or something online.

We need to give them a chance to explain.

We moved from thinking,

"Is this someone who has downloaded some terrorist material

"because they have terrorist views or sent it on to others?",

when we realised that, actually, we firmly believed

that he was planning a real-world attack.

The teenager's behaviour during interviews fuels the officers' fears

that he could be a danger to the public.

So, within 24 hours, it was clear to us

that there was potential terrorist offences

that we would need more time to investigate.

So we arrested him under the Terrorism Act,

which enables us to hold somebody for up to 48 hours

before we have to apply for a warrant to keep them for longer.

He told my officers that he didn't believe in the UK law.

The only law that he believed in was the law of Allah.

They now have 48 hours to gather enough evidence

of the extremist attacks he's planning,

or they will be forced to release a potential terrorist

onto the streets.

The subject's mother was a witness in this case.

Of course, she was really supportive and she wanted to make sure

that we understood what happened,

but she also has the best interest of the subject at heart.

So whilst she was a witness,

my team also tried to support her through this,

which was very difficult circumstances for her,

because I don't think she had any idea what he was planning

or what he could have done.

On the 25th of May, officers return to his house

and conduct a search.

So, a couple of things that were found during the search

of the subject's house that were really important to us,

a pair of tactical gloves -

so, gloves that you might, for example, see on a firearms officer -

and the same for a pair of tactical goggles.

We also then found images that he'd taken of himself

with his hood up and wearing face coverings

that led us to believe that he purchased those items for him

to use in some form of terror attack.

Officers find a camouflage jacket, a baseball cap and training shoes,

along with a notebook with notes in Arabic

on how to gain more Twitter followers.

The individual had a backpack, and in it was a Shahada flag,

so a flag largely associated with ISIS,

and, of course, a balaclava was in there as well.

So there was a certain amount of information

which supported our hypothesis

that this was an individual likely to launch a terrorist attack

and was preparing to do so.

Concerned he could be planning an act of terrorism,

DSU Philip Mills calls in the Digital Exploitation Team

to find supportive evidence quickly

by delving deeper into his digital footprint.

We could see that he had been posting some messages

about being a supporter of terrorism,

talking about terrorist acts,

talking about planning terror attacks.

We found lots of material that suggested

he'd been conducting reconnaissance videos.

He had filmed outside Stratford Court,

Stratford police station,

Stratford train station.

And he produced videos where he had attempted to zoom in

or look at police officers in certain locations in that area,

which caused us some concern about what he was planning to do.

So, in order to understand

how someone goes from talking about doing something

to actually taking active steps is a very, very difficult balance.

Now, sometimes we have a lot of people

that say a lot of things online they don't mean.

We're all familiar with that in today's social media environment.

But in this case, in addition to his statements made online

and the things he was talking about,

he was also undertaking some activities.

The officers discover a disturbing video made on the 17th of May, 2022,

at the Seventh Rifles Regiment army barracks.

They believe he was planning an Islamist attack.

He was seen standing outside the front door

of the Seventh Rifles's barracks,

and he appeared to be videoing and saying some things

into his phone at the time that he was observing the front gates

and the security of that establishment.

We identified three or four examples where he had conducted

what we would term hostile reconnaissance of potential targets

for a terrorist attack.

He had attempted to covertly film a police officer,

and in that video, he has zoomed in on them.

He's then done something whereby he's produced a little clip himself.

He's put some writing on the video, which says "Target acquired."

Counter-terrorism police have arrested a teenager from Essex

for planning an Islamist-inspired terror attack in London.

His mobile phone has revealed worrying videos of him conducting

reconnaissance of military and police targets.

Certainly, as the investigation progressed

and we saw some of the videos that he has produced,

our perception was that he was on the verge of planning something,

some kind of attack, on UK soil.

But the officers need to find definitive evidence

of a planned attack to bring a charge against him.

They continue to track the trail of data he's left behind online.

Many of his searches are of grave concern.

The pressure is on.

The 48-hours interview deadline is fast approaching.

The Digital Exploitation Team make a breakthrough.

We were able to identify

that he had registered at the Knife Warehouse the December before,

and we were also able to establish

that he'd been googling "ISIS knife attack,"

which gave us some real concerns around what his motivation

for registering with the Knife Warehouse was,

and what his intentions were going to be, were he able to buy a knife.

Armed with the supportive evidence

that the teenager is actively preparing a deadly terror attack...

..DSU Philip Mills needs to act fast to keep the teenager in custody.

So, one of the things we will do immediately

is commence a process called a warrant of further detention.

And that's where we go in front of a judge

and ask to detain this individual for a longer period of time.

Terrorism Act essentially lets us keep someone

for a maximum of 14 days.

That is extremely serious,

to detain someone, without charging them, for that period of time.

Despite extending the custody period,

there is still a possible risk to the public.

DSU Mills can't rule out that the teenager might be working

within a terrorist cell.

So the Digital Exploitation Team

focus on encrypted messaging services on the teenager's phone,

trying to identify possible co-conspirators.

We were able to identify that he'd been in contact

with a female that we're referring to as Ms A.

It certainly looked as if they were, at least, friends

or involved in some kind of relationship.

We saw some of those messages, and certainly they were alarming,

with some of the things that he had been saying

about what he would like to do, in terms of committing a terror act.

The pair shared graphic plans on how he would torture,

mutilate and behead Marines.

We know he'd been performing what we would describe as reconnaissance

outside a military barracks, and then to find messages

that he'd sent to somebody else talking about wanting to kidnap

and commit acts of torture,

you realise quite how dangerous an individual that he was.

There were a number of other relatively extreme conversations

that talked about his intent and the things that were in his mind.

DSU Mills now needs to find supportive evidence

to link these messages with a specific plot.

They discover encrypted group chats on Telegram.

One was named Group Studies.

He was seeking to join some groups

where he could ask questions about launching terrorist attacks,

where he could watch extreme ISIS videos or videos of beheadings -

all material that was adding to this large amount of evidence

which suggested that this subject was indeed a committed terrorist.

When we found those messages, things really start to click in place.

They went into a great degree of graphic detail

about what he wanted to do,

were he able to capture a police officer or a military officer

and then seek to commit acts of torture on them,

and ultimately he expressed a desire to kill them.

And clearly, when you add that with the videos taken

at the barracks, that's a deeply concerning picture for me.

Officers begin gathering CCTV to cross-reference

with the reconnaissance videos

to prove the videos were made by the teenager.

As you can imagine, recovering all that CCTV is really complex.

So once we know the subject's movements, we're able to go

and recover CCTV from across London and the Home Counties.

It was really valuable for us to be able to cross-reference that

and show that on the date and time that he'd made the video,

that we could also put him in the area from the CCTV

because it acts as corroboration, in terms of any defence he might have.

It's really valuable evidence for us.

And what we can see is that this subject

was conducting reconnaissance.

Officers desperately analyse hours of videos and CCTV footage

to give the CPS enough evidence to approve charging the teenager.

In this case, the CPS worked very closely with us every single day,

and so every single new piece of evidence is considered

by our investigation team, our senior investigating officer

and, of course, the Crown Prosecution Service.

Right up to the wire, after 14 days,

they finally feel they have enough substantial evidence

to prove the teenager was plotting an horrific Islamist terror attack.

At that point, it was clear that we could identify his ideology

and his belief system.

The Crown Prosecution Service, they ultimately agreed with us,

that we thought there was enough evidence.

The subject was charged with Section 5 of the Terrorism Act.

That's an offence that relates

to someone preparing to conduct a terrorist attack

and is one of the most serious offences in the Terrorism Act.

He didn't have any response to being charged.

The teenager remains in custody for a year,

deemed too dangerous to be released on bail.

It's noted that he seems to maintain his strong Islamist sympathies.

The defendant had been making some comments

and seeking to radicalise others within the prison system.

And of course, that's really concerning to us because it suggests

that all our views about the risk that he presents were correct,

that he's actually seeking to try and radicalise others

who may get out of prison before he does,

to try and commit a terror attack.

Following the charge and before going to trial,

the teenager decides to plead guilty.

I like to think the reason he pleaded guilty

was because we were able to put such a strong case into court.

The evidence against him was overwhelming.

20th of January 2023,

the teenager appears at the Old Bailey,

accused of preparing terror acts between December 2021 and May 2022.

At that point, he introduced a basis of what his plea was.

He suggested that he initially wanted to go to Syria,

and would only commit an attack in the UK

if he wasn't able to get there.

That wasn't accepted by the Crown.

There was nothing to suggest that he'd been trying to go to Syria,

and all the evidence that we had established at that point

was indicating that his plan was to commit an attack on UK soil.

The teenager is sentenced to life imprisonment

and given a minimum six-year tariff.

I think a life sentence for a Section 5 is quite common.

That's based on the judge's assessment

that he is a dangerous individual and that he poses a significant risk

to the public and to national security.

This is a case that shows the absolute value that we place

in contact with the public.

We only really disrupted this imminent terrorist attack

as a result of the public calling us.

This was a really thorough and meticulous investigation by my team,

to be able to establish what he'd done and how dangerous he was,

and ultimately the investigation was such that he pled guilty.

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