The YouTube killer who shot dead eight members of his school in Finland before turning his gun on himself had internet contacts with an American teenager who was planning a shooting spree in a high school in Philadelphia, it was claimed yesterday, according to a Times of London report.

The disclosure could turn upside down previous assumptions about the dynamics of school massacres. Until now, teenage killers were regarded as depressed loners whose imagination had been stoked by aggressive computer games. Now it seems that information may have been shared by potential killers over the Internet: a virtual community of young people who idolize the 1999 Columbine High School murders, said the Times of London.

Click here to read Times of London article on shared massacre plots.

“It’s highly probable that there was some form of contact between Pekka-Eric Auvinen and Dillon Cossey,” a spokesman for the cyber crime department of Helsinki police said. Dillon Cossey, 14, was arrested last month on suspicion of planning to storm his old school, Plymouth Whitemarsh. Police acting on a tipoff found a 9mm semi-automatic rifle, handmade grenades, a .22 pistol and a .22 single-shot rifle at his home. Less than two weeks later Auvinen, already a member of a shooting club, was buying his first gun — a .22 pistol — and expressing interest in a 9mm semi-automatic.

Police do not believe this to have been a coincidence. The two youths are thought to have made contact over two MySpace groups, “RIP Eric and Dylan” — a reference to Eric Harris and Dylan Klebold, who killed 12 schoolmates at Columbine — and “Natural Selection”.

Dillon Cossey used the alias Shadow 19462 on internet forums. Overweight and bullied, he had been withdrawn from Plymouth Whitemarsh and was resentful. His MySpace profile lauded the Columbine killers as heroes.The 18- year-old Finnish killer made a rambling testimony on YouTube, clearly drawing on the rhetoric used in the Natural Selection group and related chat rooms. His YouTube account — under the pseudonym Sturmgeist89 — included snippets from violent films, shots of him posing with his “beloved” pistol and tributes to other mass murderers. It was viewed 200,000 times before being closed down after the Finnish high school killings on Wednesday.

Police are trying to establish whether the Jokela massacre was in some way a copycat event or whether it resulted from an exchange of tips across the internet. Across Europe cyber-crime experts are nervous that some of the abuses on the net committed by Islamic fanatics could become a model for other marginalized groups.