Teens beat up a victim while others film and publish the event "for laughs," thus the name "happy slapping."
A British media commentator last year cited shows such as MTV's "Jackass," in which the regulars performed stunts involving self-inflicted pain and humiliation, as an inspiration behind "happy slapping." Others disputed that claim.
In America, some young people have riffed off "Jackass" in recent years by recording violent pranks and stunts and submitting them to popular Internet sites, though the "happy slapping" fad itself has yet to become a source of concern for school officials.
"I meet with principals every week, and I've never heard of it," said Bill Bond, a school safety expert with the National Association of Secondary School Principals.
The "happy slapping" fad is particularly worrying to French authorities, who have been combating youth violence after a wave of rioting, car burnings and violence last fall mostly in poor neighborhoods of Paris and other cities.
"For some youths, it is seen as a way for the poor to get revenge against the rich, who are blamed for society's problems," said Mohamed Douhane, a Paris police captain who specializes in youth crime. "It's a way for them to amuse the gallery in their neighborhoods."
Other parts of Europe already have taken action. The German state of Bavaria and dozens of schools in Ireland have barred cell phones from classrooms.
Last month, Danish courts handed down the first "happy slapping" convictions to two teens. The boy and girl had recorded an assault on a passerby in a Copenhagen shopping mall in February.
In November, a Dutch teenager was arrested in Amsterdam after confessing to hitting a woman in the head while friends filmed the incident for laughs.
In one of the most chilling cases, a report in the French daily Le Parisien on Wednesday said photos were taken of a young girl in Nice who was gang-raped earlier this year, and the images were circulated at her school.
Divisional commissioner Serge Castello, a police official in the Yvelines region southeast of Paris, said police "absolutely want to make sure that it doesn't develop" into a major problem in France -- and are intensely motivated to crack down.
"Every time we hear of an incident, we go all-out to track down the perpetrators," he said.
Others are not so sure police can prevent the spread of "happy slapping."
"I am nearly certain we're headed toward attacks that become more and more spectacular," said Pascal Lardellier, a communications science professor in Dijon and author of "Le Pouce et La Souris: Enquete sur la culture numerique des ados" ("The Thumb and the Mouse: A Study of the Digital Culture of Teens").
"Yesterday, it was a teacher, tomorrow it could be a police officer, or a judge," he said. "From the moment that the youths see the media are paying attention, there becomes this sickening process in which they try to outdo one another. It's a vicious cycle."
"They have understood intuitively that all you have to do is smack a stranger in the street, film it, put it up on a blog or the Internet, and it will garner a certain amount of success," Lardellier said.
Sounds like old-fashioned muggings taken to a new level. The taping for the and publishing for the gratification of others is troubling.
Gratuitous violence by young people is mushrooming. Youth gangs, "fight club" activities, now "happy slapping." For those that don't get out much to the theater, fight club activities are based on the 1996 novel that was made into a movie in 1999.