The founders of the website linked to the suicide of British teenager Hannah Smith, as well as two Irish girls, said they could reveal the names of anonymous bullies to the police.
Hannah, 14, was found hanged by her 16-year-old sister last Friday at their home in Lutterworth, Leicestershire, after being abused on the social networking site Ask.fm.
The suicides of 15-year-old Ciara Pugsley in Co Leitrim and 13-year-old Erin Gallagher in Co Donegal have also been linked to comments on the website.
Mark and Ilja Terebin, bosses of the Latvia-based website, said the site has the technology to identify “almost all users” and that they are committed to supporting the Leicestershire Police investigation.
They said “in extreme circumstances such as those we’ve experienced this week” they can use technology to identify those behind the taunts and “ensure this information is accessible to the appropriate legal authorities”.
Meanwhile major advertisers have withdrawn from the website, despite protests from the company that it does “not condone bullying of any kind”.
Specsavers, Vodafone, Laura Ashley, EDF Energy and charity Save the Children have all pulled ads from Ask.fm.
A Specsavers spokesman said the company had instructed Ask.fm to remove all of its adverts from the site due to “deep concerns over cyberbullying”.
Save the Children said: “We put the welfare of children first and, as a result of the tragic case of Hannah Smith, we no longer advertise on Ask.fm.”
EDF Energy also said it had asked its media agency to prevent any further advertising appearing on Ask.fm “with immediate effect”.
Ask.fm said in a statement that the company wanted to “reassure all users and parents of users that we are committed to ensuring that our site is a safe environment”.
The statement added: “We do not condone bullying of any kind, or any form of unacceptable use of our site.”
Ask.fm described the teenager’s death as a “true tragedy” and said they had been speaking to Leicestershire Police since the incident.
They went on to say that various measures had been implemented over the past few months to continue improving users’ safety, and improved reporting policies have been put in place.
The company said: “The vast majority of our users are very happy teenagers, who use Ask.fm to converse with their peers around the world about the things that interest them.
“Bullying is an age-old problem that we in no way condone – and while its evolution online is disturbing, it certainly is not unique to our site.
“We will continue to work with the appropriate organisations to safeguard against bullying on Ask.fm – and we would welcome the opportunity to align with the rest of industry and society in fighting it on a higher level.”
David Cameron has said he was looking at what action to take “to try and stop future tragedies likes this”.
The Prime Minister said: “The people that operate these websites have got to step up to the plate and show some responsibility in the way that they run these websites.
“Just because someone does something online, it doesn’t mean they’re above the law. If you incite someone to do harm, if you incite violence, that is breaking the law, whether that is online or offline.
“Also, there’s something all of us can do as parents and as users of the internet and that is not to use some of these vile sites. Boycott them, don’t go there, don’t join them – we need to do that as well.
“I’m very keen we look at all the action we can take to try and stop future tragedies like this.”
Hannah’s father, David Smith, said those who run the website should face murder or manslaughter charges and called for more regulation of social networking sites.
“There’s something not right with the world today if people can tell somebody to die so many times that they actually do it,” he said.
He told The Mirror he was “disappointed” by Mr Cameron’s comments and said the Government is ignoring the problem of online abuse.
Leicestershire Police confirmed they had been contacted by Hannah’s father about further claims of ”inappropriate postings” on Facebook.
Hannah’s sister, Joanne, told the newspaper she was being subjected to the same hateful taunts as her sister, while a Facebook page dedicated to Hannah had also been targeted.
The mother of another teenager who took his own life after reportedly being bullied on Ask.fm said she thought she understood which websites her son had visited but now admitted she “hadn’t got a clue”.
Josh Unsworth, 15, from Longridge, Lancashire, was found hanged in April after he was reportedly subjected to months of abusive messages on his Ask.fm profile.
Asked about Mr Cameron’s call to boycott such websites, Michelle Unsworth told ITV Granada Reports: “I agree that the sites should be boycotted but they won’t be completely and it’s probably the most vulnerable who will stay there.”