PARIS: French police detained five people Saturday in an investigation into an underground New Year's Eve rave party that drew at least 2,500 people in western France despite a coronavirus curfew and other restrictions.

French Interior Minister Gerald Darmanin tweeted that actions by police around the site at Lieuron, in Brittany, “led to the end of the illegal party without violence” on Saturday morning, 36 hours after it began. He said a judicial investigation has been opened to identify and prosecute organizers.

Prefect Emmanuel Berthier, head of the local state authority, said in a news conference Saturday that police officers issued at least 1,200 fines, including 800 under virus-related rules for not respecting the curfew, not wearing a mask and illegally taking part in a gathering.

Hundreds of people were also fined for using illicit drugs and sound equipment and power generators were confiscated, Berthier said.

Ravers from France and abroad converged on a hangar in Lieuron on Thursday night to party into the New Year. Officials said ravers attacked the police on the first night, torching one police vehicle and slightly injuring three officers with volleys of bottles and stones.

Video images showed lines of ravers' trucks and cars leaving on Saturday morning.

The party took place despite France’s nationwide night-time curfew, which seeks to dissuade people from gathering during the pandemic.

The aid group Techno+ distributed masks, anti-virus gel and health advice inside the party. One volunteer there, who only gave her name as Ombline, said the pandemic has been very hard on youths and something positive was needed to fight the depression that many are facing.

The Regional Health Agency of Brittany warned that party-goers had a high risk of spreading the virus and urged participants to self-isolate for a week and get a test in seven days.

France has reported more than 64,000 virus-related deaths.