A 15-year-old boy was injured Tuesday morning in front of a college in Limay, Yvelines, stabbed in a brawl involving three alleged attackers, two of whom were arrested, the police said.

A "settlement of account". The facts took place shortly after 8 am in front of the college Albert-Thierry of this popular city bordering Mantes-la-Jolie. A "settlement of account" between "rival gangs" broke out and "three perpetrators assaulted the victim", educated in this college, according to a police source.

Three stab wounds in the back. One of the three assailants, a 13-year-old girl attending another college in the city allegedly stabbed the victim three times in the back before fleeing, according to the same source. She was arrested soon after in the school where she is educated, Galileo College. The knife was found by the investigators in the bathroom of the establishment. One of the other two alleged perpetrators, aged 14, was arrested in the middle of the morning. The third, identified, had not yet been arrested at midday.

A supervisor also struck. According to the first elements of the investigation, an altercation whose origin remains unknown would have burst in a bus between them and the victim and would have continued before the establishment. A supervisor of the college, witness of the scene, also "took shots" and is slightly injured on one shoulder, according to firefighters. She was transported to Mantes hospital, as was the teenager, "seriously injured," according to the same source. He was transferred in the morning to the Necker Hospital in Paris. The police station of Mantes-la-Jolie is responsible for the investigation.