TV's "Jackass" and "Dirty Sanchez" are blamed for the growing "happy slapping" craze in Britain, where children film each other attacking strangers. The films are then posted on the Internet or exchanged by cell phone. Dr. Graham Barnfield, head of media at the University of East London, said the craze had a striking similarity with stunts in the MTV and Channel 4 shows, the BBC reported Thursday. Deputy Prime Minister John Prescott said he had narrowly avoided falling victim to "happy slapping" when approached by a group of teenage boys with a video camera in a motorway cafe. An MTV spokesman said the series made clear that "no attempt should be made to recreate" stunts in the programs.