"In the note he said he hated mankind and the human race. And that he had been planning this since 2002," Mr Neulaniemi said. The note went on to say "the solution is Walther 22", a reference to the gunman's Walther .22 calibre handgun, ABC reported.

The Independent reported that Saari lived alone with his cat and police were having trouble getting in contact with his relatives. But former classmate Susanna Keronen said Saari bore no resemblance to the loner profile of many mass murderers. "He was happy, a social guy - there was nothing exceptional - he got along with people well and he was not lonely. He had friends [and was easy to talk to]," she said.

In his profile on social networking site IRCgallery, Saari billed himself as a committed misanthrope and touted war and revenge. He spent his last hours on the internet, having logged on to IRCgallery on Tuesday morning before leaving for school and opening fire on his classmates.

Saari, an atheist, said on MySpace.com, that he was interested in meeting friends and networking. But on other sites, he mulled the final solution to the problems of mankind and aired darker thoughts. On his YouTube profile, Saari listed death metal and electronic bands among his favourite music, and quoted lyrics from a song called War, by the group Wumpscut: "Whole life is war and and whole life is pain and you will fight alone in your personal war." He also listed horror as his favourite movie genre and said his hobbies were computers, guns, sex and beers.

Saari also mentioned his gun on a dating site, and wrote that he was looking for a woman but did not want children. Saari did not have a previous criminal record, The Guardian reported.

- with Reuters