Obsessions of a maniac who called himself the Terminator: Plymouth gunman posted videos on YouTube of himself pumping iron and ranting about his life before going on murder spree

Staring intensely into the camera, Jake Davison signed off his final video on YouTube with the chilling words: 'I am a Terminator.'

Within weeks, the 22-year-old virgin would enact his bloody fantasies with appalling consequences.

In a 12-minute rampage, the gunman murdered his own mother and four strangers, including a three-year-old girl.

The gun massacre – the worst in a decade in the UK – left Plymouth residents questioning how a loner with seemingly serious mental health problems was allowed to have a firearms licence.

Shockingly, it emerged yesterday that the behaviour of the apprentice crane operator had been of concern for some time to those close to him, including his mother Maxine and father Mark – who had reportedly begged the NHS for help and even allegedly contacted the police saying he should not be allowed to keep a gun.

Within hours of the shootings, disturbing videos emerged online in which the 17-stone weightlifter moaned about being 'defeated in life' and talked about the violent sci-fi films starring Arnold Schwarzenegger.

He said: 'The whole premise of the Terminator movies is that you know everything is rigged against you, there's no hope for humanity, you know, we're on the brink of extinction.

'These machines are unstoppable killing machines that can't be beaten, can't be outsmarted, but yet humanity still tries to fight to the end.

'I know it's a movie but, you know, I like to think sometimes I'm a Terminator or something and despite reaching almost total system failure, he keeps trying to accomplish his mission.'

Recording his final video on July 28, Davison said: 'I'm beaten down and defeated by f****** life. That drive I once had, that's gone.'

The loner had described himself as an 'incel' – a reference to the 'involuntary celibate' movement, a radical group of misogynistic young males who spend their lives ranting online about women and are of growing concern to police.

Recording videos in a small bedroom he likened to a 'prison cell', Davison spent his days agonising over why he had never had a girlfriend or even been kissed.

Obsessed with sex, he fired off scores of messages to incel groups asking why he was constantly rejected on dating sites and bemoaning his lack of experience of love as a teenager.

Rambling virgin Davison said he hoped working out would help him lose weight and become more attractive to women

Revealing he had not spoken to a girl since he was 17, Davison considered himself a virgin loser with nothing to live for.

He wrote of his loneliness and despair, saying he had been 'forgotten about'.

'I used to be OK with being a virgin too, but when you get older and the inferiority complex kicks in and the feeling of despair and missing out occurs,' he said.

'Try being an unemployed, autistic, poor, sexually frustrated male with tons of health issues, no social circle and being stuck in government housing with my mother for years on end, having missed out on so much in life.

Videos left online for hours

Social media giants were accused last night of allowing extremists time to 'glorify' the Plymouth gunman after his accounts were left online for hours after the killing.

Jake Davison's YouTube channel and Facebook page, which revealed a young man obsessed with firearms and his struggle attracting girls, attracted thousands of comments before being removed. Much of the content referred to the 'incel' community.

Among the sick comments were users branding the 22-year-old a 'new hero' and calling him a 'supreme gentleman', used to refer to US mass shooter Elliot Rodger.

Campaigners accused firms of allowing the community to thrive on their platforms for years. The Centre for Countering Digital Hate said Davison's rhetoric would have been amplified through the platforms' algorithm.

He posted several videos in the weeks before the attack in which he blamed his troubles on not having a girlfriend.

His YouTube account was taken down on yesterday morning. But in the 18 or so hours between the killings and the removal, incels had flocked to leave positive comments.

Davison's Facebook account also had received more than 2,000 comments before it was made unavailable.

Imran Ahmed, of the CCDH, said: 'He was glorified while YouTube dragged their heels.' A YouTube spokesman said: 'We have strict policies to ensure our platform is not used to incite violence.'

'Not being able to do the hobbies and things I enjoy as I don't have a car, I am socially isolated and a black sheep who barely interacts with anyone other than a few people at work.

'It's not just sex and teen romance I feel I missed out on, I feel I missed out on the entire teenage experience. Since leaving school I don't have any friends.'

Born in Plymouth, he was raised with his older brother and sister by their single mother Maxine, with whom he had a difficult relationship, writing online: 'Feel my mother has played a role in being a male virgin.'

Diagnosed with autism as a child, Davison was sent to Mount Tamar special school in Plymouth, where he was said to have been a 'disruptive' influence on his peers.

Jess Wallace recalled: 'My boyfriend went to school with him and said he was pretty shy and quiet and would talk about how cool Americans are, and the idea of having a gun collection.'

Another woman related to a former classmate said: 'He was well-known for his anger issues.'

After leaving school, Davison described feeling positive as he embarked on a career working in construction scaffolding before an ankle injury sent him spiralling into depression. He admitted online that his 'mental, physical and emotional health' had been deteriorating for two years.

He wrote of his frustration at being unable to get a doctor's appointment and revealed he tried a cocktail of supplements and steroids and even considered drugs like cocaine.

Consumed by self-loathing, the recluse posted regular questions such as 'Should being ugly be considered a disability?' and recorded scores of videos and selfies discussing his weight issues and fear of being too fat to get a girlfriend.

Lonely and bored, he described himself as a 'computer addict with nothing else to do for many years'.

He wrote: 'When you have been a recluse for as long as I have, you search up and go on pretty much every subject on the internet. I can't think of a subject I haven't dabbled in on the internet – technology, politics, space, exploration, astronomy, LGBT transgender movies, comics, video games, military, special forces guns, weapons, tanks, jets, nuclear power, futurism, transhumanism, drugs, biology, history.'

In a desperate search for like-minded individuals, he signed up for IncelTV on YouTube.

Spurred on by others in the community, Davison said he had 'overdosed' on 'black pill' – an incel philosophy centred on the belief that success with the opposite sex is determined by genetics.

He wrote: 'Inferiority complex of being a virgin for almost 23 years and the panic of getting older is crippling.' Incel culture has been associated with killings and acts of violence, particularly in the US, where Davison had fantasised about living.

Elliot Rodger became a spiritual figurehead of the incel movement when he murdered six people in Isla Vista, California, in 2014 aged 22 – the same age as Davison.

Jake Davison's mother Maxine and other relatives are claimed to have begged the police and NHS to help him with mental health problems. Davison started his rampage by kicking down her door and shooting her dead

Sophie Martyn, 3, and her father Lee, 43, (pictured above) were shot at random as Plymouth incel gunman Jake Davison entered Biddick Drive and fatally killed the pair who were walking up the road

Davison then moved on towards a nearby wooded area where he shot and murdered dog walker Stephen Washington, 59,

66-year-old Kate Shepherd was Davison's final victim, and was gunned down by Blush hair salon in Plymouth

Before his rampage, Rodger had posted a video on YouTube saying he wanted to take revenge on women for rejecting him.

Within hours of Davison's killings, other incel internet users had built what was described as an online 'shrine' to him yesterday.

Shortly before the attacks, Davison called for a 'Government-funded incel social programme or rehab centre' to get them to do group activities 'to build confidence and self-esteem and getting them out of their depressed mindset'.

Among his ideas were group therapy, activities such as rock climbing and 'taking away computers, phones, internet to detox from social media and the internet'.

But trapped in his bedroom during lockdown, Davison's despair only grew.

Yesterday it emerged that he had liked nearly 800 videos on YouTube pointing to an obsession with US gun culture, violent video games and weightlifting.

He boasted to followers that he held a shotgun licence, writing: 'It would be good if there were more ranges and clubs too.

'I have a section SGC (shotgun certificate) but would properly have a FAC (firearms certificate) as well if there were more ranges... as soon as I get a car, which should not take too long, I will apply for my FAC.'

Within recent weeks, Davison's thoughts had turned to death and knives. He wrote online: 'Machetes are awful weapons... most are cheaply made and lack the cutting power to do any real damage like actual swords do.

'If you actually look at machete attacks, videos and news reports, more often than not they only manage to cut and lacerate skin.

Police work near the scene on Biddick Drive following the shooting in the Keyham area of Plymouth yesterday evening

A police car at the scene on Biddick Drive today following the shooting in Keyham, Plymouth, yesterday evening

'They rarely have the weight and sharpness to cut through bone and skull. They are good for cutting through bush, not cutting limbs and heads... best sword for zombie would be a two-handed great sword which would cut limbs clean off and penetrate skull easily.'

In another post on 'mass shootings' he referred to the Texas clock tower shooting in America in 1966 and the Hungerford massacre in Berkshire in 1987.

Davison wrote: 'There are a lot more guns in Europe and the UK than people think.'

Yesterday, neighbours revealed the Davison family's desperate pleas for help.

Donna Croft said: 'His poor mum has only just got cleared of cancer. His sister was a harmless soul, she was in the same class as my son.

'The dad even begged the mental health team to assess him but they basically said they couldn't be bothered and said they were too short of staff to come out.

'So not have only the mental services on this country let these poor families down, they could prevented this to happen.

'People like that need 24/7 help. How he got a gun to kill these people is crazy.'