Baffled parents lack the technical skills to protect their children from internet risks, a report says today.

Researchers found many adults had no idea how their offspring used mobile phones and the internet.

These "alarming" knowledge gaps make it difficult for parents to protect youngsters from online porn, violence and other unsuitable content, according to children's charity NCH.

Chatrooms, emails and text messages are other areas where vulnerable youngsters can be at risk from "inappropriate" contact with other users.

Children may also be on the receiving end of internet and mobile phone-based scams or hard-sell tactics, the NCH report warns.

Its survey found that 67 per cent of parents didn't know what a blog was and only one per cent thought their children used them.

In fact one third of the 11-to 16-year-olds questioned regularly used the internet for blogging, where they uploaded personal details and information.

More than half (53 per cent) of children said their parents never or hardly ever supervised their internet use.

By contrast, 81 per cent of parents claimed they knew what their children were doing online at all times.

Four in ten parents didn't know how to block their children from viewing certain online content.

Nearly half (46 per cent) of the 11- to 16-year-olds questioned were confident they could get around internet blocks which parents use to deny access to certain websites.

Seven out of ten parents admitted knowing less about mobile phones than their children, while 57 per cent said the same thing about the internet.

NCH new technology advisor John Carr said: "Children are pretty clued up when it comes to technology but they often lack the worldly wisdom to steer them away from its potential hazards.

"That's where parents come in. But our research shows they need to increase their knowledge if they want to protect their children."

The NCH report was based on research done in partnership with Tesco Telecoms.

It is based on a survey of 1,003 parents and 1,003 youngsters, aged 11 to 16 years, carried out last month by researchers from ICM.