Mark Davison says he is ‘sorry and ashamed’ of his son Jake who who shot dead five people before killing himself

The father of a man who shot dead five people in Plymouth has said he told police he did not believe his son should have a shotgun because he was concerned about his mental health.

Mark Davison said he was ashamed of his son Jake, 22, who shot dead his mother and four other people before killing himself in August.

Police watchdog investigates why Jake Davison was put on a rehabilitation scheme and had weapon returned

The Plymouth gunman was not charged or cautioned after he carried out a vicious assault in a city park last year, but instead was allowed to take part in a four-month rehabilitation scheme, it has emerged.

Jake Davison’s legally held shotgun was confiscated after he began the Pathfinder scheme and a worker from it found out he had the weapon and informed Devon and Cornwall police. But the shotgun was handed back last month after he finished the programme.

Exclusive: Jake Davison seen pacing around convenience store for more than five minutes on day before attack

Police increasingly believe that anti-women propaganda may have fuelled anger in the Plymouth gunman before his attack, with his links to the “incel” movement a main strand of their investigation.

Jake Davison, 22, shot dead his mother and four other people on 12 August. It emerged that he had engaged with extremist ideology including the “involuntary celibate” movement, though this is not considered to be enough for security officials to declare the mass shooting as a terrorist attack. Counter-terrorism officers continue to aid the investigation as detectives trawl through the attacker’s electronic devices.