The teenage outcast who killed eight people and himself in a high school shooting in Finland may have had Internet contacts with a Pennsylvania youth accused of plotting a possible school attack, Finnish police said Monday.

Police said material seized from the computer of Pekka-Eric Auvinen suggests the 18-year-old communicated online with Dillon Cossey, 14, who was arrested in October for allegedly preparing a possible attack at Plymouth Whitemarsh High School in Pennsylvania.

"I consider it quite possible that he has been in contact" with Cossey, Rabbe von Hertzen, a detective in the case, told The Associated Press.

He declined to provide details saying the investigation was on going.

Auvinen killed six students, a nurse and the principal Wednesday in Tuusula, about 30 miles north of the Finnish capital, Helsinki. He then shot himself in the head, and died hours later at a hospital.

Von Hertzen said Finnish police had not yet been in contact with their U.S. colleagues about a possible link between the two teens.

In Pennsylvania, Montgomery County District Attorney Bruce Castor said he told his detectives to run the name of the Finnish shooter through the computer seized from Cossey, who admitted in juvenile court to planning an attack at a suburban Philadelphia high school.

"None of us really think that there's going to be a lot here, but we're going to check it out," said Castor, who heard of the possible connection from media reports.

Tipped off by a boy Cossey tried to recruit, Pennsylvania authorities searched his home last month. They found a rifle, about 30 air-powered guns modeled to look like higher-powered weapons, swords, knives, a bomb-making book, videos of the 1999 Columbine attack and violence-filled notebooks.

Cossey's attorney, J. David Farrell, said he doubted his client had been involved in planning the Finnish attack.

"Knowing my client as I have gotten to know him, I would be surprised if he were engaged in any true planning or encouraging behavior to an individual in Finland who was planning some sort of school attack," Farrell told CNN.

Finnish investigators have said Auvinen left a suicide note for his family and foreshadowed the attack in YouTube postings.

On Monday, Von Herzen said Auvinen is believed to have written the suicide note on Nov. 5, suggesting he had planned the attacks for at least two days.

Police have described Auvinen as a bullied teenage outcast consumed with anger against society.