- See more Daily Mail on Google - save us as a Preferred Source
This is the moment an 18-year-old son remained strangely calm as he was arrested for murdering his mother hours after dog walkers found her body in undergrowth.
asserted
walkers → see → undergrowth
Tristan Roberts, of Prestatyn, North Wales, was put in handcuffs by officers outside his home after Angela Shellis, 45, was discovered dead in the Morfa Nature Park.
asserted
Shellis → put → Park
Roberts, who hated women and was obsessed with violence, beat his teaching assistant mother to death in a planned attack with a hammer in October last year.
asserted
who → hat → October
He kept Ms Shellis prisoner in her bedroom, recording her four-hour ordeal before luring her into isolated woodland by pretending he was allowing her to get help.
But Roberts then delivered the fatal blows and left her body in the reserve, before returning home around 6.30am – where he was later arrested by North Wales Police.
asserted
he → keep → Police
Video footage of his arrest at 1.20pm features in a new episode of Channel 4 documentary '999: What Happened Next', which is airing on Mondays at 9pm.
The programme also looks at the evidence that led to him being arrested and his eventual jail sentence of at least 22 and a half years at Mold Crown Court in March.
asserted
him → feature → March
A clip shared with the Daily Mail shows Roberts being told to 'turn around and face the wall' outside his home, before being told to drop a water bottle he is holding.
asserted
he → share → bottle
Tristan Roberts, 18, is arrested in Prestatyn in October 2025 after his mother was found dead
Angela Shellis, 45, was found dead in undergrowth beside a footpath near a nature reserve
Tristan Roberts, 18, was jailed for at least 22 and a half years at Mold Crown Court in March
asserted
Roberts → arrest → March
The officer then tells Roberts: 'Just going to put you in handcuffs for now, okay?
asserted
officer → tell → handcuffs
Have you got anything on you?'
asserted
you → get → you
Roberts replies: 'No.
asserted
Roberts → reply → ?
Am I detained or arrested?'
asserted
I → detain → ?
An officer then says: 'All in order at the moment, Tristan came to the door and he came out, so we'll wait for other officers to get here before we go into the address.
asserted
we → say → address
Recalling his arrest in the documentary, Detective Constable Claire Owen, who worked on the case, said: 'He came out of the house calmly.
'
asserted
He → recall → house
He allowed himself to be handcuffed.
asserted
himself → allow → ?
Potentially we thought he may have been in shock or very young and didn't understand what was going on.
uncertain
what → think → shock
'
She added that Roberts asked officers: 'Is the body that's been found my mum?'
asserted
that → add → officers
DC Owen continued: 'His reaction just seemed very at odds with what you would expect with an 18-year-old who had just been arrested for murder.'
The police investigation began earlier that day when a dog walker called 999 at 8.30am, reporting that they had found a woman's body in the undergrowth and a large trail of blood along a gravel path.
Detectives secured the scene and deployed drone units.
asserted
Detectives → continue → units
They also found a crutch, balaclava and a pair of black gloves – but did not know the victim's identity at that stage.
asserted
They → find → stage
Then just after 1pm, police received a further call from a relative of Ms Shellis who was raising concerns for both her and Roberts, who had barricaded himself into the home.
asserted
who → receive → home
Roberts answered 'no comment' to questions put to him during subsequent police interviews
The hammer found at Roberts's home in Prestatyn, which he had earlier bought on Amazon
Police found a pair of black gloves at the murder scene beside a footpath near a nature reserve
Police were told Ms Shellis had been using a crutch because of a knee injury – and headed to the home, by which time family members had managed to get inside.
During that period officers also obtained CCTV of Roberts and Ms Shellis leaving the home at 3.20am, with Roberts carrying a rucksack and Ms Shellis with a crutch.
asserted
Roberts → answer → crutch
Police thought this was significant enough to arrest Roberts, which they did – and detectives then worked to establish his exact movements.
asserted
detectives → think → movements
DC Owen said: 'We had to keep an open mind as to who committed this offence.
asserted
who → say → offence
We strongly suspected Tristan at that point, but equally it's possible that he'd left Angela in the nature reserve and someone else had done this.'
asserted
someone → suspect → this
Detective Superintendent Andy Gibson, the senior investigating officer, added: 'So at this point in time we've got CCTV evidence of Tristan's movements.
'
asserted
we → investigate → movements
But we still need to fill evidential gaps.
asserted
we → need → gaps
Investigators then found footage of the mother and son going over the local railway crossing, heading towards the Morfa site – before Roberts returned to the home.
asserted
Roberts → find → home
Soon after that Roberts left the home alone again, following the same direction but this time carrying a bag – believed to have bleach and other fluids to forensically clean the scene.
asserted
Roberts → leave → scene
The contents of a carrier bag found inside Roberts's home address, including a hammer
Roberts shared messages about hating women online in the months before the murder
Police outside Roberts's home in Prestatyn in October last year following the murder
In the months before the murder, Roberts – who was diagnosed with autism and ADHD - had boasted online about his intention to kill.
asserted
who → find → intention
He also discussed being motivated by a 'hatred of women', writing: 'I do hate girls, are you OK with that?'
asserted
you → discuss → that
An AI tool advised him that a hammer would be the best murder weapon for 'a non-experienced killer', and also provided help on how to clean up after the killing.
Roberts's older brother Ethan had even texted his mother when she failed to answer the phone on the day of her murder, asking: 'Just call me for a second - so that I know you are alive.'
Roberts posed as her, replying: 'I think I am alive [laughing emoji]'.
asserted
I → advise → her
After killing Ms Shellis, Roberts posted online: 'I've just had the craziest day', adding that he had 'beat the s*** out of her' and 'smashed her skull in so hard with a sledgehammer'.
asserted
he → kill → sledgehammer
On the day of the arrest, a family liaison officer - who cannot be named for police operational reasons – was assigned to support relatives of Ms Shellis.
asserted
who → name → Shellis
This officer told the documentary: 'Angela was a mother, a daughter herself, she was one of three siblings and she was part of what was a really close family who chose to spend a lot of time together.
'
asserted
who → tell → time
She absolutely worshipped both of her sons and did above and beyond what anyone would do for them.
asserted
anyone → worship → them
She was known as kind and sweet and a lovely person and they all knew each other very well and they all knew Tristan very well.
asserted
they → know → Tristan
They all knew the battle Angela was manning to try and make sure that he got the right support and that he took that support - but there was a deterioration in his behaviour.
asserted
he → know → behaviour
Ms Shellis's sister Sarah Gunther said in court that she wanted her to be remembered as 'a mum who never gave up, no matter what life threw at her', adding that the family had 'fought so hard' in an attempt to get Roberts 'the help you needed'.
'999: What Happened Next' airs on Channel 4 on Mondays at 9pm
asserted
What → say → pm
The Aporia
