The attack at Peck Park in the community of San Pedro may have involved more than one shooter and appeared to have started with a dispute between two parties, Los Angeles Police Capt. Kelly Muniz said at an early evening news conference.
"Some weapons were found," she said.
Four people were hospitalized in critical condition, Cmdr. Jay Mastick, the commander of the Los Angeles Police Department's Harbor Area, said earlier, NBC News reported.
The injured were ages 3 to 54, Los Angeles Fire Capt. Erik Scott said at the news conference.
Muniz said an impromptu car show at the park was the "draw" for as many as 500 people who gathered before gunfire rang out. "It was not necessarily permitted," the captain said.
MA/PR