OAKLAND, Calif. (AP) — Fifteen people were shot during a Juneteenth celebration in Oakland, California, police said Thursday.

The violence broke out Wednesday night during an event at Lake Merritt that was largely peaceful, with as many as 5,000 in attendance, until a sideshow involving “motorbikes and vehicles” took place around 8:15 p.m. on the north side of the lake.

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A fight broke out down the street from the sideshow and a crowd gathered in the area of the fight, police said. At least one person was taken into custody for assaulting an officer.

Another person was injured during an assault that occurred after they walked across the hood of one of the vehicles involved in the sideshow and the occupants’ got out and attacked them, Oakland Police Chief Floyd Mitchell told a news conference.

No suspects have been taken into custody in connection with the shooting, Mitchell said.

Investigators found more than 50 shell casings at the scene.

At least one gunshot victim was in critical condition. The victims’ ages ranged from 20 to 30 years old.

Paul Chambers, the police department’s strategic communications manager, said earlier that as officers tried to get the crowd to safety several people struck OPD officers.

A large police presence included as many as two dozen police vehicles and multiple ambulances at the scene, KTVU-TV reported. Police said 28 officers and four sergeants were at the scene to monitor the event.

Participants in the celebration were seen getting verbal with police with some people criticizing police response, saying they didn’t respond quickly enough when people were injured, KTVU reported.

In 2021, a shooting during a Juneteenth celebration at Lake Merritt left several people injured and a 22-year-old San Francisco man dead.

Police said the investigation of Wednesday night’s shooting was ongoing.