Children are being exposed to sex and violence on websites their parents think are safe, a new survey has found.
Research carried out for the NSPCC found that half of 11 to 17-year-olds admit to having seen pornography or graphic violence on social media, apps and games.
Nearly eight out of ten of the children asked also admitted to breaking the rules on social media and signing up for it before they were 13.
Some of the websites which parents thought posed a low risk to children were rated as high risk by the kids themselves.
The NSPCC’s Head of Policy and Public Affairs, Alan Wardle, said that many websites “treat 13 year olds like adults, which is inappropriate”.
He warned that children have seen “sexual behaviour, self-harm, violence” and the “live streaming of sex”.
Chief Executive of the charity, Peter Wanless, said it was “vital” that parents sit down with their children regularly and talk about social media.
He added: “More than 60 per cent of young people we asked said social media platforms need to do more to keep children safe.
“These companies need to take more responsibility for keeping children safe online.”
Earlier this year, the Government revealed new plans to restrict distressing online sexual content which could be seen by children.
Conservative ministers say pornography has “never been more easily accessible online” and exposure to the material could damage children’s emotional and psychological development.
Adult users of such content may be forced to prove their age in future, as a way of blocking under-18s from seeing online pornography.