More than 100 young people were arrested in the Paris suburbs on Halloween — after messages circulated around social media calling for a “purge” of the police force, according to new reports.

Gangs of masked teens stormed through the city center of Lyon, harassing cops and passersby, smashing store windows and setting trash bins on fire.

In one case, in the deprived Seine-Saint-Denis area north of Paris, youths robbing a grocery store attacked police with acid, according to Denis Jacob of the police union Alternative Police. A sportswear store was also looted.

Authorities needed to use tear gas to control the rioters, reports said.

The chaos was incited by a Snapchat message shared by a 19-year-old man from Grenoble who encouraged others to gang up in neighborhood groups, go out on the street and fight, France 24 English reported.

Though he did not directly mention violence against police, related posts started popping up around social media — some calling on young people to burn everything in sight and attack cops with firecrackers and stones, the station reported.

The riots were inspired by the Hollywood horror film franchise “The Purge,” which depicts a dystopian America where all crime is made legal for one day a year.

The original poster ultimately admitted it was all a joke and urged the public not to commit any violent acts — but he was arrested anyway, cops said.

He was released on Tuesday pending trial on Nov. 28.

“Halloween must remain a celebration,” Interior Minister Christophe Castaner told reporters on Thursday. “The purge is not a joke, the purge is a threat.”

Although the violence turned out to be less severe than a year ago, 15,000 cops were deployed Wednesday night in anticipation, Castaner said.

Halloween is not traditionally celebrated in France, though the influence of American films and TV series have caused it to become more visible since the late 1990s.

With Post Wires