A teenager who idolised mass murderers has been convicted of attempting to purchase a gun and ammunition with intent to endanger life.

Kyle Davies, 19, saw those behind the massacre at Columbine High School and Norwegian extremist Anders Breivik as his “poster boys”, prosecutors said.

He used the cryptocurrency Bitcoin to purchase a Glock 17 handgun and five rounds of ammunition from an online gun dealer on the dark web, ordering it to his family home in Gloucester.

A Glock pistol and ammunition shown in evidence during the trial of Kyle Davies
A Glock pistol and ammunition shown in evidence during the trial of Kyle Davies (South West Regional Organised Crime Unit/PA)

Homeland Security officers intercepted the order at Newark Airport in New York and tipped off local police, who arrested Davies after delivering a dummy package to his home.

Davies insisted he had purchased the gun and ammunition in order to kill himself and denied he was planning a mass shooting.

But when officers searched his bedroom, they discovered handwritten notes and a USB stick containing more than 1,000 pages relating to explosives and massacres.

A jury unanimously convicted him of attempting to possess a firearm with intent to endanger life and attempting to possess the ammunition with intent to endanger life following a two-week trial at Gloucester Crown Court.

Judge Paul Cook told Davies: “You have been found guilty in relation to both counts of the indictment.

A shopping list which was shown in evidence during the trial of Kyle Davies
A shopping list which was shown in evidence during the trial (South West Regional Organised Crime Unit/PA)

“You are facing a significant period of imprisonment but I need to have further information about you and the risk that you pose.”

He will sentence Davies on a date to be fixed.

During the trial, jurors heard how Davies was an ordinary A-level pupil planning to go to university but had developed a “deep and persistent” interest in mass murders.

On June 18 last year, Homeland Security intercepted a package addressed to Davies at his home in Gloucester and found it contained a viable Glock 17 and ammunition.

Two days later, an undercover officer from Gloucestershire Police delivered a dummy parcel to his property at 2.30pm, with firearms teams bringing Davies outside nine hours later.

Until police began searching the teenager’s bedroom, they had no idea of the motives or inspiration behind him purchasing the weapon.

Davies had used software to clear browsing data each time he closed his laptop but crucially was using it at the time of his arrest, meaning officers were able to access his online activity that day.

This revealed searches for Columbine, as well as how to clean a Glock 17 and searches relating to UK firearms officers.

A USB stick found in his bedroom contained more than 1,000 pages relating to massacres and explosives, including how-to guides.

Police discovered a note on Davies’ bedside table entitled Gotterdammerung, or twilight of the gods, which listed equipment required for a mass shooting event.

This matched a similar document called “Phase One”, featuring links of where to purchase the items.

He had drawn 77 stick people to represent those murdered by Breivik in one page of a school book, while another was scrawled with “Hello Mr Policeman”.

One featured the words “This one Mr Policeman” with an arrow pointing to writing about his mental state.

Detective Inspector Kevin Till, of the South West Regional Organised Crime Unit, said: “The depth of research Davies had carried out and the extent of his planning under what he himself termed ‘phase one’ leaves us in no doubt he was intending to follow in the footsteps of the murderers he idolised.

“The intervention by Homeland Security at Newark Airport undoubtedly led us to a very dangerous individual.

“A meticulous investigation, closely supported by forensic experts and the CPS, has clearly shown his intent to harm others and, ultimately, ensured he never had the opportunity to move on to ‘phase two’.”

Items on Davies’ lists included a gas mask, trench coat, gloves, boots, body armour and a leg pistol holder as well as ingredients for explosives.

A handwritten note found in the bedroom of Kyle Davies
A handwritten note found in the bedroom of Kyle Davies (South West Regional Organised Crime Unit/PA)

After he was arrested, Davies told police: “I know, I know. You should have just shot me. I haven’t technically possessed anything anyway.”

The teenager pleaded guilty to two counts of evading the prohibition on the importation of firearms and ammunition, as well as two counts of making indecent images of children.

But he denied attempting to possess the weapon and ammunition with intent to endanger life, claiming the only life he wanted to end was his own.

Prosecuting, Anna Vigars QC told the jury: “He wasn’t preparing for suicide.

“He was perhaps expecting to die at the end of his own lethal killing spree and take as many others as possible out with him on the way.”

Jurors were told that Davies’ parents had no idea of his online activity.

He had previously spoken of being bullied and had been found on a motorway bridge at the age of 15, the court heard.

Howard Phillips, of the Crown Prosecution Service, said: “Davies’ notes did not identify a target and did not demonstrate an ideology or aim that would support a charge under terrorism legislation.”