The leaders of an anti-bullying motorcycle club in northern France have been arrested on charges of threatening a school headteacher and his deputy.
The president of the Black Shadow North WC club and his wife were questioned by police in the town of Auchel, 65km (40 miles) west of Lille.
The alleged offenses – which they deny – include threatening to bundle the headteacher into the boot of a car.
The row arose from reports of violence between pupils, prosecutors say.
The Black Shadow North WC club is one of several biker clubs that have emerged in France to combat bullying in recent years.
Members accuse police and school officials of not doing enough to tackle the problem. According to health experts, over 10% of French pupils experience bullying by the age of 16.
The confrontation in Auchel originated in a complaint last month by a mother who said her teenage daughter was being targeted, media say.
The bullying allegation was not confirmed by authorities. But feelings were running high after a teenager from a neighbouring school took her own life in early November.
Prosecutors say the president of Black Shadow North WC went near the school in Auchel to demand sanctions against the alleged offenders.
The prosecutor’s office says the biker and his wife threatened to come back “with dozens of bikers to put the headteacher in a car boot and take him across the Belgian border because of his lack of action”.
The accused, who deny any wrongdoing, are due to appear in court on Monday.