C4 to cover marathon masturbation session

Channel 4 is to screen footage from Britain's first ' marathon masturbation' event.

Hundreds of sexual exhibitionists - both male and female - are expected to attend the charity event in Central London early next month.

A 60-minute documentary, entitled W***athon, will follow in the autumn.

'We feel this is exactly the type of provocative and mischievous programming that Channel 4 should be covering in the 11pm slot,' said Andrew MacKenzie, the broadcaster's factual entertainment commissioning editor. 'Masturbation is something many people do but it is something not many people talk about.'

But John Beyer, head of Mediawatch, which campaigns against 'offensive' issues in the media, condemned the planned broadcast.

He said: 'Channel 4 is a public broadcaster and, under the Communications Act, it should not carry material-which would cause public offence. '[Broadcasting watchdogs] cannot do anything until people complain after the programme is shown, so we are calling for Culture, Media and Sport Secretary Tessa Jowell to intervene.'

Scotland Yard said it was unlikely to intervene because obscenity laws 'were always a matter of interpretation'.

The W***athon is the brainchild of the San Francisco-based Centre for Sex and Culture, which holds similar events in the US to help safe-sex groups.

Prizes will be on offer for those who have the most orgasms and those who can masturbate the longest - the record is eight-and-a-half hours.

Faked orgasms are not allowed and competitors who break this rule three times can expect to be disqualified.

However, the invigilators, who will also be naked, have not said how they expect to spot 'fakers'.