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LONDON - The posting on YouTube of a clip announcing a school shooting in Finland before it happened shows how self-shot videos have become the favoured means for modern killers wanting to get their message across.
The nature of 24-hour media means such videos are also likely to get worldwide attention very quickly in a way which letters never could.
Seven children and the school principal were killed when a fellow pupil opened fire at a school in southern Finland, hours after a clip posted on video sharing website YouTube predicted a massacre there.
The YouTube video, set to a hard-driving song called "Stray Bullet", shows a still photo of a low building that appears to be the Jokela High School.
The photo breaks apart to reveal a red-tinted picture of a man pointing a handgun at the camera.
"Go back 50 years or 25 years, they wrote letters and now they've moved onto YouTube," Mike Berry, a professor in criminal psychology, told Reuters.
"He's just using today's modern facilities. Young people use YouTube instead of a pen and paper.
"I don't think this will produce copycat situations but what I do think is that people who want to make a message will see this as a new avenue."
The YouTube video, entitled "Jokela High School Massacre - 11/7/2007", was posted by a user called Sturmgeist89.
"I am prepared to fight and die for my cause," read a posting by a user of the same name.
"I, as a natural selector, will eliminate all who I see unfit, disgraces of human race and failures of natural selection." "Sturmgeist" means storm spirit in German.
The user's account has since been suspended.
Virginia tape
Earlier this year Cho Seung-Hui killed 33 people, including himself, at Virginia Tech in the United States and mailed a video explaining his actions to US broadcaster NBC during the killing spree.
Unlike the Finnish case, where the video appeared on a freely accessible video sharing site, NBC had to choose whether to air the footage or not. Its decision to do so triggered a debate about whether the diatribe should have been made public.
Access to media was very different a decade ago.
In 1996, the man behind Britain's worst gun killing spree, Thomas Hamilton, sent letters to local officials, politicians and Queen Elizabeth to express his anger at perceived injustices before killing 16 children and their teacher in Dunblane, Scotland.
YouTube has been criticised in the past for carrying clips which show violence and bullying. It takes down those found to breach the site's guidelines.
Ian Brown, a research fellow at the Oxford internet Institute said he did not think the use of YouTube was a driving factor in the Finnish case.
"New technologies like the internet get used by a very wide range of people and unfortunately including in events like this," he said. "Before this, many people who committed very serious crimes would get publicity through newspapers. This is how the mass media works in the 20th and 21st century."
Online video sharing sites like YouTube mean controlling violent or disturbing images is becoming increasingly difficult.
In the aftermath of the Virginia Tech shooting, some experts suggested that access to cell phone cameras means a deadly attack might one day be broadcast over the internet in real time.
- REUTERS