AI bot told teen to use a hammer to kill his mother: Loner callously tortured and executed his devoted parent after becoming lost in toxic online world that indulged his brutal fantasies

A teenage boy with a hatred of women was advised how to kill his mother by anĀ AIĀ chatbot.

The disturbing details behind the murder of teaching assistant Angela Shellis came as her son Tristan Roberts, 18, was jailed for life yesterday for bludgeoning her to death with a hammer.

Roberts had posted misogynistic messages and boasted of his chilling intent to kill on a controversial chat forum linked to other murders.

He then asked an AI tool for tips on which weapon to use and how to clean up afterwards. It told him a hammer would be best for ‘a non-experienced killer’.

The case sparked fresh fears about the dark corners of the internet and the growing influence of artificial intelligence, with shocking research suggesting eight out of ten chatbots were willing to assist in planning violent attacks, including school shootings, religious bombings, and high-profile assassinations.

In the weeks leading up to his mother’s death, Roberts, who was diagnosed with autism andĀ ADHD, was repeatedly banned from controversial gaming messaging app Discord, due to the extreme content he was posting.

Roberts posted about murders, violence, misogyny, weapons, and his intention to kill his mother.

But he was able to set up at least 16 new accounts and continue his women-hating diatribes.

Tristan Roberts, 18, (pictured being arrested at his home after his mother's body was found on October 24) was jailed for life yesterday for bludgeoning his mother Angela Shellis to death with a hammer
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Tristan Roberts, 18, (pictured being arrested at his home after his mother’s body was found on October 24) was jailed for life yesterday for bludgeoning his mother Angela Shellis to death with a hammer

He asked an AI tool for tips on which weapon to use to murder his mother Angela Shellis (pictured) and how to clean up afterwards. It told him a hammer would be best for 'a non-experienced killer'
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He asked an AI tool for tips on which weapon to use to murder his mother Angela Shellis (pictured) and how to clean up afterwards. It told him a hammer would be best for ‘a non-experienced killer’

Roberts had previously posted misogynistic messages (pictured) and boasted of his chilling intent to kill on controversial chat forum Discord, which has been linked to other murders
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Roberts had previously posted misogynistic messages (pictured) and boasted of his chilling intent to kill on controversial chat forum Discord, which has been linked to other murders

He then turned to DeepSeek, a Chinese AI search engine already banned in Australia from government devices and systems, for advice on carrying out his crime.

The chatbot initially refused to engage but when he asked again, simply claiming he was researching a book on serial killers, it aided his plotting.

He asked questions such as ‘how do I remove any trace of blood, of DNA from the killer or victim?,’ how to incapacitate a ‘female aged 45’ and about cutting body parts.

Imran Ahmed, founderĀ of the Centre for Countering Digital Hate, which was behind the research that found chatbots happy to indulge such fantasies, said: ‘This is yet another tragic case of an AI chatbot helping a vulnerable young man move from expressing violent intent to acting on it.

‘Even the most basic safeguards can be bypassed with minimal effort.

‘How many more people need to die before the tech industry implements strong safeguards, real accountability, and urgent intervention?’

Jailing him for life, with a minimum of 22 years, Judge Rhys Rowlands told Roberts that his mother’s terror during her last moments could notĀ be imagined.

‘It was a truly awful way for someone to die,’ he said. ‘It was made all the more dreadful that her attacker was her own son.’

He said that, despite his autism and ADHD diagnoses, Roberts knew exactly what he was doing that night.

A Discord spokesman said the app took decisive action, including removing content and banning bad actors.

‘He’s bought a knife and a hammer,’ Angela texted. ‘Why?? Is he planning to hurt me?’Ā 

By James TozerĀ 

For 18 years, Angela Shellis ‘fought tirelessly’ for her son Tristan.

But the ‘unbreakable’ love she felt for herĀ deeply troubled younger boy – as well as his successful university undergraduate elder brother – was to be betrayed in the cruellest manner imaginable.

Diagnosed with autism and ADHD, Tristan Roberts spent hours a day in a toxic online world where he could give vent to his most depraved fantasies.

He was so divorced from reality – and obsessed with violence and mass murderers – that he became fixated on the notion that his ‘devoted’ mother was to blame for his unhappiness.

Fuelled by unjustified anger and poisonous misogyny, which he spouted on the controversial gamers’ messaging app Discord, RobertsĀ began plotting to kill her.

In a chilling glimpse into the insidious power of AI, the teenager turned to the technology’s unmonitored might for tips on what kind of weapons a ‘non-experienced’ killer should use.

Then, Roberts turned 18. He didn’t spend his birthday drinking with friends.

Instead, he visited a local branch of The Range store chain, where he bought a knife and disposable razors, showing ID to prove he was 18 – the required legal age.

He held his 45-year-old mother prisoner in her own bedroom, repeatedly attacking her with a hammer (pictured) and strangling her
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He held his 45-year-old mother prisoner in her own bedroom, repeatedly attacking her with a hammer (pictured) and strangling her

He then led her to a nature reserve (pictured, the pair walking there, captured on CCTV footage) and bludgeoned her to death with the hammer - which he had bought on Amazon for £20
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He then led her to a nature reserve (pictured, the pair walking there, captured on CCTV footage) and bludgeoned her to death with the hammer – which he had bought on Amazon for Ā£20

He spent hours a day in a toxic online world where he could give vent to his most depraved fantasies. Pictured: A message he posted on online chat forum Discord

He spent hours a day in a toxic online world where he could give vent to his most depraved fantasies. Pictured: A message he posted on online chat forum Discord

He was so divorced from reality – and obsessed with violence and mass murderers – that he became fixated on the notion that his 'devoted' mother was to blame for his unhappiness. Pictured: A message he posted on Discord about serial killer TV series Dexter

He was so divorced from reality – and obsessed with violence and mass murderers – that he became fixated on the notion that his ‘devoted’ mother was to blame for his unhappiness. Pictured: A message he posted on Discord about serial killer TV series Dexter

The purchase concerned the cashier, who kept a copy of the teenager’s receipt. The next day he bought another knife.

Two weeksĀ later, he enacted his callous plot – putting his mother through a four-and-a-half-hour ordeal of unspeakable horror.

Roberts recorded every moment of it. From the initial assault to the final fatal blows. Mercifully for Angela’s family, those moments weren’t played to court.

It was agony enough for them to hear how Roberts held his 45-year-old mother prisoner in her own bedroom, repeatedly attacking her with a hammer and strangling her.

He then led her to a nature reserve and bludgeoned her to death with the hammer he had bought on Amazon for £20.

What could possibly have motivated such brutality?Ā That is a question that continues to haunt Angela’s family.

Roberts, who had a fascination with serial killers, including TV series Dexter and the movie American Psycho, has offered no explanation; in police interviews he responded ‘no comment’.

In a note on his laptop a week before the killing he spelt out his twisted desire for ‘vengeance’ against his mother, saying he was ‘Not Tristan Roberts, but Alex’.

Self-pityingly he described his ‘entire life’ as ‘a s***show of f****** hell, just hell, abandonment, betrayal, bullied, nearly froze to death, physical effort, suffering’.

‘All of it and most caused by oneĀ person, and not myself.

‘And now that one person, not out of sadistic pleasure or malice, but out of revenge, justice, vengeance and… to move forwards in life, I must take the weight off my back.

‘Even if it hurts. There is no use living anymore if I don’t do this. I am already dead.’

In notes he wrote before the murder he said he was motivated by ‘hatred of women’. One Discord post read: ‘I do hate girls are you OK with that?’

The platform has been accused in the US of harbouring radical communities including white supremacist far-RightĀ groups.

Conservative activist Charlie Kirk’s suspected assassin, Tyler Robinson, is also reported to have been active on the site.

In reality, Roberts’ ungrateful and self-centred attitude was a cruel and insulting inversion of the lifelong sacrifices Ms Shellis had made for both her sons.

Roberts has offered no explanation for his brutality; in police interviews (pictured) he responded 'no comment'
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Roberts has offered no explanation for his brutality; in police interviews (pictured) he responded ‘no comment’

In a note on his laptop a week before the killing, Roberts (pictured) spelt out his twisted desire for 'vengeance' against his mother
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In a note on his laptop a week before the killing, Roberts (pictured) spelt out his twisted desire for ‘vengeance’ against his mother

But in reality, Roberts' ungrateful and self-centred attitude was a cruel and insulting inversion of the lifelong sacrifices Ms Shellis (pictured) had made for both her sons
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But in reality, Roberts’ ungrateful and self-centred attitude was a cruel and insulting inversion of the lifelong sacrifices Ms Shellis (pictured) had made for both her sons

Her devotion to her boys is clear from her own social media accounts, peppered with pictures of them.

‘Home is where my boys are,’ reads one post.Ā ‘I will never understand how some parents live every day knowing they have a child out there they rarely bother about and just get on with their life withoutĀ a care in the world.’

After separating from the boys’ father, she had moved back from Bedfordshire to the seaside town of Prestatyn in her native North Wales so they could benefit from the support of relatives.

A qualified teacher, described by relatives as having ‘a heart full of love and kindness’, Angela took a lower-paid job as a teaching assistant at Rhyl High School so she could spend more time with her sons. That Roberts needed help was clear.

In childhood, he was referred to Children and Adolescent Mental Health Services. He attended mainstream schools but ‘struggled’ and hadĀ a history of disruptive behaviour.

But while he was diagnosed with autism and ADHD, to this day, professionals have detected no recognised mental health disorder – relatives now suspect he ‘manipulated’ doctors.

Adolescence was turbulent: he spent time in hospital, in homeless accommodation and a period with his father in Milton Keynes.

What support Angela sought – and with what, the court heard, ‘limited success’ – will doubtless become clearer with time.

Denbighshire County Council said yesterday that it and ‘partner organisations’ had referred the case to North Wales Safeguarding Board and could not comment.

What is known is thatĀ the mother and son relationship became ‘strained’. Family members, too, were worried about Roberts’ deteriorating behaviour after the family moved to Prestatyn.

In February 2025 he was given a six-month referral order by Llandudno youth court for possession of a bladed item in a public place and shoplifting.

Neighbours reported him behaving aggressively towards them, and overheard him shouting in the family’s semi-detached house.

It is a devastating feature of this case that both Angela and her elder son, Ethan, had begun to suspect the threat Roberts represented towards her.

As Mold Crown Court was told, on October 17 – four days after Roberts had turned 18 – the worried mother messaged a social worker and friends, stating that he had bought a knife and a hammer.

In one note on her phone she asked: ‘Why?? What does he need these for? Is he planning to hurt me, himself, what? Who? Why? FFS.’

Ethan too was concerned; before going back to university, he set up wireless-enabled cameras inside the family home.

In the weeks running up to the murder he used Chinese AI search tool DeepSeek to ask for tips for a 'non-experienced killer'. Pictured: Gloves found at the crime scene
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In the weeks running up to the murder he used Chinese AI search tool DeepSeek to ask for tips for a ‘non-experienced killer’. Pictured: Gloves found at the crime scene

He soon put his murderous plan into practice. Along with weapons, he bought a balaclava, facemasks, overalls and clingfilm. Pictured: A carrier bag and its contents found at Roberts's address upon his arrest
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He soon put his murderous plan into practice. Along with weapons, he bought a balaclava, facemasks, overalls and clingfilm. Pictured: A carrier bag and its contents found at Roberts’s address upon his arrest

The attack began at around 11pm and lasted until 3.30am. Preying on her devotion, Roberts convinced his mother to leave the house, under the pretence she could have her injuries treated. Pictured: Ms Shellis's mobile phone, which was found by police at her home
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The attack began at around 11pm and lasted until 3.30am. Preying on her devotion, Roberts convinced his mother to leave the house, under the pretence she could have her injuries treated. Pictured: Ms Shellis’s mobile phone, which was found by police at her home

He ordered her to put on a balaclava (pictured, found by police at the scene) – to restrict how far her blood was spread, police suspect – then tricked her into taking a 'shortcut' through a nature reserve, where he left her to die
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He ordered her to put on a balaclava (pictured, found by police at the scene) – to restrict how far her blood was spread, police suspect – then tricked her into taking a ‘shortcut’ through a nature reserve, where he left her to die

But unknown to either of them,Ā Roberts’ plans were escalating.

In the early hours of October 18, he posted messages on Discord stating that he had been standing overĀ his mother holding a hammer as she slept but did not use it.

The next morning, she wrote a note on her phone reading: ‘OMG… I did not sleep well at all… and Tristan kept coming into my room too – why? Am I safe in my room tonight?’

Meanwhile, Roberts’ posts on Discord were becoming ever more disturbing.

In one chat he boasted about being able to chop a bear apart with a weapon.

Another said: ‘She is gonna just vanish off the earth. I already tried everything else. Now it’s time.’

In a third he wrote: ‘I canĀ kill her bare-handed. I only want to make it brutal and make sure I don’t mess up with an axe.’

His accounts were repeatedly taken down for violating the platform’s policies against abusive and threatening content and his posts deleted.

But Roberts, who wasn’t in education, kept thousands of screenshots (recovered by police after the murder) and simply set up new user names – a total of 16 different accounts.

In the weeks running up to the murder he used Chinese AI search tool DeepSeek to ask for tips for a ‘non-experienced killer’, including whether he should use a knifeĀ or a hammer.

After it refused to engage, Roberts tricked it by lying that he was writing a book about serial killers.

Once Ethan had gone back to university for the new term, Roberts put his murderous plan into practice.

Along with weapons, he bought a balaclava, facemasks, overalls and clingfilm.

His mother was particularly vulnerable because she was off work and using crutches due to a leg injury.

On the evening of October 23, he made a brief voice recording in which he said that he was ‘Alex’ – believed to be his murderous alter ego – and wasĀ going to kill his mother.

The attack began at around 11pm and lasted until 3.30am. ‘This is the moment we are doing it,’ he said. ‘We are going to hit her with a sledgehammer.’

When he was arrested later that day, Roberts had barricaded himself into his bedroom. He calmly asked officers: 'Is the body you found my mother?'. Pictured: Police at his home address
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When he was arrested later that day, Roberts had barricaded himself into his bedroom. He calmly asked officers: ‘Is the body you found my mother?’. Pictured: Police at his home address

As killer Roberts (pictured) was given a life sentence yesterday, devastated relatives were still struggling to comprehend the tragedy
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As killer Roberts (pictured) was given a life sentence yesterday, devastated relatives were still struggling to comprehend the tragedy

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Ā Mother was bludgeoned to death by her ADHD son, 18, after he posted misogynistic messages on Discord

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Ms Shellis was conscious before pleading in a ‘calm and firm voice’ for him to phone 999 for medical help.

She even offered to ‘back him up and say that he had not known what he was doing’, prosecutor Andrew Thomas KC said.

But, preying on her devotion, Roberts convinced her to leave the house, under the pretence she could have her injuries treated.

He orderedĀ her to put on a balaclava – to restrict how far her blood was spread, police suspect – then tricked her into taking a ‘short cut’ through a nature reserve.

There, he took the sledgehammer out of his rucksack and rained down blows on her, leaving her to die.

He returned home alone at 5.35am and was filmed on a doorbell camera leaving again 50 minutes later, swinging a carrier bag thought to have contained bleach to clean the murder scene.

He was thwarted by the presence of dog walkers and he returned home.

Later that morning he logged straightĀ back on to Discord, writing: ‘I’ve just had the craziest day.’

He said that he had ‘beat the s***’ out of his mother, and described how he had ‘smashed her skull’.

Angela’s body was found just after 8.30am, but it took police several hours to establish her identity.

Relatives were worried and tried to contact her – but Roberts sent messages from her phone to say she was laid up with a ‘bad throat’.

Ethan sent his mother’s phone a message asking: ‘Just call me for a second… so that I know you are alive.’

Roberts – posing as theirĀ mother – replied: ‘I think I am alive [laughing emoji]’.

When he was arrested later that day, he had barricaded himself into his bedroom. He calmly asked officers: ‘Is the body you found my mother?’

The murder weapon – a Ā£20 ‘mini sledgehammer’ bought on Amazon – was seized at the home.

As he was given a life sentence yesterday, devastated relatives were still struggling to comprehend the tragedy.

In a powerful victim impact statement to the court, Ethan said their mother had done anything and everything for Roberts ‘his whole life’.

‘Mum never gave up on him. I don’tĀ know how he could do this to anyone, let alone the one person… that would do absolutely anything for him,’ he said.

He felt ‘haunted’ by anger as well as guilt that he was unable to protect his mother.

Her sister, Sarah Gunther, said she wanted her sister to be remembered as ‘a mum who never gave up, no matter what life threw at her’.

Addressing her nephew directly, she told him how the family ‘fought so hard to try and get you the help you needed’.