One in five of Britain's children are being bullied via their PC or mobile phone, according to charity organisation NCH.
In its annual review the charity found that the most common form of bullying was via text message, but that nearly 10 per cent of children had also been threatened by email or in an internet chat room. One in 10 children had been photographed with a cameraphone as part of the bullying.
"Historically, most bullying took place at school, or between home and the school gates," said the report entitled Putting U in the Picture.
"As soon as a child got home they could shut the door behind them and find sanctuary. Home was a place where the bullies could not reach them, but mobile bullying has changed that."
The survey found that half of all bullying goes on outside school hours, and that 42 per cent of children had suffered attacks after 9pm. Over a quarter of all the children surveyed never tell anyone about the attacks, and fewer than a quarter talk to their parents about the problem.
"Text messages are what they talk about most; we have not seen too many calls about pictures being sent as yet. The key message for children is not to suffer in silence, but to tell someone."
The spokesman urged children to save all threatening texts and emails and to keep a diary of attacks to be used as evidence.
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