HOWZAT

"What worries me is that when you start entering a virtual world, as these young people are doing on this Bebo site, you lose the reality of loss, the actual consequences of what you are talking about and the horrible reality of death - in particular, the consequences on family and friends and the whole lack of a future for these young people, which is absolutely tragic," she told BBC Radio 4's Today programme.

"It is absolutely bizarre to think that a memorial wall gives you a reason for ending your life, cutting yourself off from a real future that would involve friends, family, marriage, building a home, building a career - all these real things that stretched in front of these young people - all for the ephemera of something on an internet wall," she said.

"It absolutely defies belief."

Darren Matthews, director of the Bridgend Samaritans, which deals with many of South Wales's most depressed people, said that some were attracted to suicide as a way of achieving fame in the modern media, although he said that social networking sites were not themselves to blame.

"We are in real danger of creating this negative effect where people who are loners feel: 'I can go out with a bang - everyone will know that I have gone.' That is not just the internet. That is in many different types of the media," he said.

Bebo issued a statement today encouraging its users in need to contact the Samaritans, with which it says it has developed a relationship. On its site, a page entitled 'Stamp Out Suicide' provides a number of links which users in need can click on in order to get help.

"The loss of any young life is always distressing. We will work closely with the authorities to provide any assistance which will help them with their investigations," a Bebo spokesman said.

The social networking site, founded in 2005, claims to have more than 10 million unique UK users and a total worldwide membership of more than 38 million worldwide. Users can set up their own homepages, blogs, post on users' walls, and post photographs.

It attracts a much younger audience than social networking sites such as MySpace and Facebook, with most Bebo users in their teens while Facebook and MySpace users are predominantly in their 20s and 30s.

David Gunnell, Professor of Epidemiology at the University of Bristol, said he feared that discussions about suicides on social networking sites could create copycats.

"Young people are more likely to see and read items concerning suicide on the internet than they are in newspapers," he said. "One can extrapolate from wider research on responses to newspaper reporting that a medium like Bebo will have an impact on suicidal behaviour in young people."

South Wales Police fear that the reason could be simpler. One officer said: "They may think it's cool to have a memorial website. It may even be a way of achieving prestige among their peer group."