After a year of name-calling and isolation, it seemed like a gesture of peace. The two girls who had been making Helen Mee’s life a misery came up to her at school and asked for her e-mail address, saying they wanted to be friends after all. Soon, they were all chatting away to one another from their bedrooms in Birmingham on the MSN service used by thousands of schoolchildren. But then the messages flashing on Helen’s screen turned nasty.

“It started with things like ‘you’re a ginger rat’, but it’s just got worse and worse,” said Helen, 14. “Last week they wrote ‘u deserve to b shot in da f****** head see if anyone would mizz u’ and ‘I dnt even wna luk at u ya mak me sik’. I was really shocked — the girls wheedled me into thinking we were mates.”

Helen’s is far from a lone case. According to new academic research, more than 15% of children fell victim to cyber-bullies last year. The most common forms are abusive text messages and e-mails, but The Sunday Times recently reported a new and worrying form of internet bullying — under investigation by police at a top independent school — that involved holding any victim down and forcing them to watch extreme websites featuring scenes such as torture, bestiality and child pornography.

“Children’s bedrooms are like mission control with all the computers, mobiles, games consoles, sounds and images all working in harmony,” said Ralph Surman, a teacher at Cantrell primary school in Nottingham. “But this kit also gives bullies some very diverse tools. They can avoid confronting the person and they can be impersonal, cold, static and distant in the way they attack their victims.”

Some 85% of children aged 8-15 are believed to own a mobile phone, which has triggered a form of “happy slapping”, in which pupils — usually boys — are beaten up and filmed on a phone. The footage is then posted on the internet or forwarded as a message to “entertain” groups of friends.

Blaine Cross, 12, was talking to friends at Hawthorn high school, Pontypridd, when a group of bullies came up behind him and knocked him over. “They all started kicking me and punching me from both sides and I just curled up into a ball and put my hands around my head to stop them,” he said. “I looked up and saw one of the boys was holding a phone and filming, they passed it round and they all had a laugh while they were watching.” His school said it was working with the Cross family to “address any issues”.

More than 1.4m children under 16 use the social networking website Bebo, with hundreds of thousands more using its competitors MySpace and Piczo. These sites allow youngsters to meet and chat with friends, but they also reflect the users’ lives in the real world — as well as friends, there are bullies, victims and rival groups taunting one another. It emerged last week that Casey Knibbs, a 13-year-old schoolboy from Warwickshire, had hanged himself after being taunted on Bebo.

“There’s been fights through Bebo. It happened with a group of my friends and some girls from another school,” said Harley Roberts, 15, from Sydenham, south London. “Two months ago a girl left a comment on my friend’s site saying ‘you’re ugly’, and then my friend wrote ‘you’re a s***’ on her site. In the end there was five of us and five of them, all writing on each other’s sites. I was getting about 10 a day. I got called ‘fat and spotty’ and we called them ‘anorexic w******’.”

The secrecy of the internet can inspire cruel creativity. Children can hack into one another’s websites, pose as each other and make anonymous threats. At Tonbridge school in Kent, bullies set up a fake home page for one boy that accused him of bestiality and incest.

Before the days of the internet, a child could escape playground bullies at the end of the school day, but cyber-bullies can follow them into their homes. “When I was a kid, you closed the street door behind you and home was a sanctuary. Now that is gone,” said John Carr, internet consultant at NCH, the children’s charity.

Many schools have only recently begun to take internet security seriously. Some have reacted by installing software that blocks access to obscene websites. Other programs, such as Securus, work by alerting staff whenever a pupil types an obscene or banned word. The result has been that many bullies now keep their online attacks for the evening, when policing children’s use of the internet at home is far more difficult.

Parents must take into account the risks, but will be reluctant to use the kind of snooping software favoured by schools. If they monitor their children’s phone and internet use too closely, or try to stop them altogether, this will seem like punishing the victim.

“We did a national survey and 30% of the children being bullied said they didn’t tell anybody,” said Carr. “A lot were worried their parents would take away their mobile phone or stop them using the computer.”

Nonetheless, over the next few months, parents can expect a barrage of advice about how to protect their children from web bullies and other online abusers. The government has commissioned an advertising campaign, Bebo is preparing an education package of online videos for parents and teachers, and the Home Office is drawing up guidelines for responsible use of social networking websites.

They will all advise parents to become more internet-savvy and devote the same attention to their children’s online welfare as they do if they are bullied in the playground.

“This need not mean prying into every corner of a child’s online life,” said a source on the Home Office taskforce.

“But parents should learn how to talk to children about their online friends and get to know which ones might pose a danger, in the same way they get to know about the friends their sons and daughters hang out with after school.”

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