A teenager suffered a broken jaw in an assault that was watched by a paying audience of schoolchildren and filmed for internet broadcast, in what French police said is a variation of “happy slapping”.

Up to 40 adolescents were invited to see the 15-year-old victim being beaten up by another boy of the same age, on a housing estate in Lyons, in central France.

The children paid a fee, which ranged from chewing gum to €1, according to education officials in the city.

The fight, which followed an altercation at the College Vendôme secondary school, Lyons, was filmed and posted on the internet. It was the latest in a series of “happy slapping” incidents, a phenomenon that arrived in France about two years ago.

Police said the incident had broken new ground by turning violence into a live show.

The time, place and outcome of the assault were stage-managed, say officers, who are concerned that other teenage gangs could seek to carry out copycat attacks.

The victim is being treated in hospital for injuries described as “very serious”.

The boy alleged to have carried out the assault was suspended by the school and faces questioning along with the teenager who filmed the incident.

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