RIVERSIDE (AP) — Seven people were shot and wounded early Monday during a Halloween party at a Southern California nightclub, police said.

The shooting was reported at a nightclub called Sevilla in the city of Riverside that had promoted a weekend of Halloween-themed events, including a Sunday night rap show billed as “The First Purge” or “The Purge Election Year.”

Two victims found by officers inside the nightclub were taken to a hospital for treatment. Five other victims later arrived at local hospitals with gunshot wounds, police said.

Police watch commander Sgt. Ryan Wilson said none of the victims’ wounds were life-threatening.

One witness who did not want to be identified told KTLA-TV that he was dancing when gunshots rang out.

He said he saw multiple people firing guns and that there was a bottleneck of people trying to get out of the exit as he hid behind the bar and prayed.

The initial police investigation shows that a fight broke out at the club and those involved began exchanging gunfire both inside and outside, said Officer Ryan Railsback, a department spokesman.

Investigators are looking into whether the shooting was gang-related, Railsback said.

The investigation was being handled by the department’s robbery-homicide and gang intelligence units.

Riverside is about 55 miles (88.5 kilometers) inland from Los Angeles.