Social networking sites such as Facebook and MySpace should introduce tougher rules to stop users posting abusive information about other members, according to a survey.

A Mori poll conducted on behalf of the Press Complaints Commission (PCC) revealed that nine out of 10 people favour tighter regulations to protect members against abuse of their privacy through the posting of unapproved material.

Some 42 per cent of 16 to 24 year-olds who use social networking sites indicated that they knew someone who had been embarrassed by material posted without their approval.

The report also highlighted fears over media intrusion. Almost 80 per cent of respondents said that they would be less likely to post their details online if they thought that the media might use the information.

Under the current system of self-policed regulation social networking sites set their own terms and conditions which forbid the posting of harmful, unlawful, obscene or threatening information about other users.

"This clearly has implications for the PCC, which has always had the task of deciding where to draw the boundaries between what newspapers and magazines may legitimately publish and what can rightly be considered private," said Sir Christopher Meyer, chairman of the PCC.

"The challenge remains the same for online editorial content, including material taken from social networking sites."