KAUHAJOKI, Finland -- Finland could face more copycat school shootings, the country's police chief warned Thursday as investigators probed a growing list of eerie similarities between two deadly rampages in less than a year.
Police Commissioner Mikko Paatero told Finnish MTV3 that police would increase their monitoring of YouTube and other Internet sites where the gunmen in both shootings posted clips foreshadowing the attacks.
On Tuesday, 22-year-old Matti Saari killed 10 people before shooting himself in a fiery massacre at his vocational college in western Finland. In November, 18-year-old Pekka-Eric Auvinen fatally shot eight people and himself at his school in southern Finland.
Asked whether he thought the attacks would inspire more school shootings, Paatero said "I badly fear it's possible."
In neighboring Sweden, police arrested a 16-year-old-boy for illegal weapon possession after receiving a tip about a suspicious clip he had posted on YouTube.
Police raided the teen's home in Koping, central Sweden, after seeing the YouTube clip, according to police spokesman Borje Stromberg. He couldn't immediately confirm the contents of the clip.
Swedish police urged people to report any offensive, threatening or criminal material they find on the Internet.
"There may also be reasons to inform police about material on the Internet that can be seen as warning signals of planned crimes," national police said Thursday on its Web site.
In Finland, investigators said Auvinen and Saari likely bought their guns at the same place and could even have been in contact with each other.
"Their actions seems so similar that I would consider it a miracle if we did not find some connecting link," Jari Neulaniemi was quoted as telling the Finnish news agency STT.
Both gunmen posted violent clips on YouTube before the shootings, both were fascinated by the 1999 Columbine school shootings in Colorado, both attacked their own schools and both died after shooting themselves in the head.
The government pledged to tighten Finland's gun laws and keep mentally unstable people from obtaining firearms after Saari's rampage at the Kauhajoki School of Hospitality, 180 miles (290 kilometers) northwest of Helsinki.
Interior Minister Anne Holmlund said the government was working on a proposal to restrict gun laws by giving police greater powers to examine gun applicants' health records. Saari acquired a permit for his weapon in August, police said.
Finland has deeply held hunting traditions and ranks _ along with the United States _ among the top five nations when it comes to civilian gun ownership. After the previous massacre, the government had pledged to raise the age for buying a gun from 15 to 18 but never did so.
The government also called for an investigation into police handling of the case. After an anonymous tip, police had questioned Saari on Monday about YouTube clips that showed him firing a handgun. But police said they found no reason to hold him.
Police were searching for a person who appeared to have filmed some of Saari's YouTube clips but said there was no indication Saari had an accomplice.
Those slain by Saari include eight female students, one male teacher and one male student. A 21-year-old woman that Saari shot in the head is still hospitalized after having two operations.
Neulaniemi said there was no indication that Saari had singled out women, but women bore the brunt of the attack because most of the trade college's students were women.
Police said Saari had left a message saying he had planned an attack for six years and wanted to kill as many people as possible.
Associated Press writers Matti Huuhtanen and Jari Tanner in Helsinki and Karl Ritter in Stockholm, Sweden, contributed to this report.
LawOfficer.com Editorial Director A.J. Heightman comments:
The school shootings in Finland should alert all public safety professionals to new patterns emerging in school shootings and terrorism. Attacks are now being preceded by bold and obvious statements on sites such as YouTube that should alert law enforcement agencies to intercede before it s too late.
It s also clear that schools are in the sights of those who want to inflict fast, unchallenged carnage on a large easy-to-access population. As readers will see in the October Supplement The War on Trauma that will be posted on LawOfficer.com, organized terrorist groups have planned and carried out attacks on schools in many countries outside the United States, particularly middle schools where the size of the individuals presents little resistance and threat, and have made it clear that they plan on carrying out similar attacks in America.