Posts and interactions from Plymouth gunman Jake Davison’s social media accounts show a clear disdain for his mother, whom he called “vile” in the lead-up to his attack.

Davison, 22, shot and killed his 51-year-old mother Maxine Davison, also known as Maxine Chapman, at a house in Biddick Drive in the Keyham area of the city on Thursday evening, before killing four others and himself.

His social media activity will form a key part of the investigation as officers attempt to establish a motive for the attack, Chief Constable Shaun Sawyer told reporters on Friday.

In interactions online, he only spoke about his mother negatively, calling her “abusive”, “disgusting” and “vile”.

They also offered insight into the mind of a man who was interested in guns and America, and anxious about sex and motivation.

– MotherDavison brought up his mother on several occasions in different Reddit posts while complaining about the state of his life.

In one post, from a few months ago, he spoke of living in a “council/government house” and not having to anyone to interact with apart from his “vile mother”.

In another, dated 10 days ago, he answered a question asking “What do incels think of their mother?” by saying “cant stand her” (sic).

A lengthy post from five days ago Davison spoke of his mother being “a great example” of a woman who never thinks she is the problem.

It went on: “She has never apologized in her life and very few women ever do for anything she genuinely believes she has been a great mother who ‘tried her best’.

“She has never taken responsibility for anything ever even when she was 100 percent in the wrong being horrible it was never her fault and because she is my mother rather then put up with her s*** i appeased her cleaned up said sorry to her even when it wasn’t my fault.

“But you best believe i will not tolerate this EVER with any other women that comes into my life her being both my mother who im forced to live with due to money reasons is the ONLY reason i put up with it.”

In another, from a month ago, he bemoaned having to live with his “disgusting abusive mother” for “years on end”.

– Guns

Davison engaged with a number of gun-related videos and accounts through his YouTube channel, named Professor Waffle.

One of his previous cover photos on Facebook was also that of a statue depicting a man holding a gun.

A lengthy Reddit post from his account further demonstrates his obsession with firearms.

In the comment, which was posted around three weeks ago, Davison declared “mass shootings are new phenomena that cannot be directly blamed on guns”.

“Plus there are lot more guns in europe and the UK then people think,” he added.

Police confirmed he was a licensed gun holder.

– Incel culture

Incel – meaning “involuntary celibate” – culture has amassed a following online among some men who feel they are being oppressed by women due to a perceived lack of sexual interest.

The online subculture has been linked to several mass shootings in the past, mostly in the United States and Canada.

Davison’s social media use suggests an obsession with the culture, subscribing to one YouTube channel called Incel TV.

In one of his YouTube videos, Davison described his anxiety at failing to have sex during his teenage years, and posts to various groups on Reddit show he was concerned about the issue.

In one post, he wrote “being a virgin lately just makes me not want to do anything”, while another read “whenever I use tinder which I properly shouldn’t makes me feel inferior…

“It seems i never get any matches and from what i have read up most guys don’t either.”

In one post to the subreddit r/IncelExit – a subreddit for people who want to find a way out of incel culture – Davison wrote “there should be a government funded incel social programme or rehab Centre of some type”.

– America

Davison’s Facebook page declared he was from Phoenix, Arizona – though the truth of this is uncertain. Nonetheless, his social media activity demonstrated an interest in the US.

Old Facebook photos of his included an eagle in front of an American flag, as well as a post appearing to back Donald Trump.

The post featured a picture of the former president with text reading: “In America, we do not seek to impose our way of life on anyone, but rather to let it shine as an example for everyone to watch.”

Davison’s Facebook cover photos also include an image of the Lexington Minuteman monument, a statue in Massachusetts of 18th-century American colonial farmer and soldier Captain John Parker.

The effigy is frequently used to represent the minuteman, a civilian force during the American Revolutionary War who were so-called because they were self-trained to be armed and ready to fight at a minute’s notice.

Davison discussed gun culture in the US at length in one Reddit comment, displaying an apparent in-depth knowledge of the type of weapon used in previous mass shootings.

– State of mind

In what appeared to be Davison’s final YouTube upload before Thursday’s incident, he spoke of being “beaten down” and “defeated by life”.

In the recording, dated July 28, the 22-year-old discussed exercise and said: “I was doing a session just now and I was thinking ‘what am I doing this for?’

“Has it changed my life? No. Do I feel any better any more? No. Do I get any enjoyment from working out any more? No… When I was 16, 17, 18 I had that passion you know.

“I’m surprised I even made it this far to be honest,” he said, adding, “for the most part it’s just been me against the world.”

Another of his Reddit posts read “How to get over feeling its too late and the best years are behind me.”

– Aftermath

Mr Davison’s YouTube account was taken down on Friday, with a notice reading: “This account has been terminated for violating YouTube’s Community Guidelines”.

His Facebook profile picture attracted more than 2,000 comments in the hours following Thursday’s incident before his page was made unavailable.

His Reddit account at the time of writing is still viewable.