A witness told KABC that the shooting happened in the back parking lot of the church after an argument erupted between family members inside the building. The fight spilled into the parking lot, where shots were fired, the television station reported.
"Words were said inside the service that somebody took offense to," Sheriff's Lt. Derrick Alfred told KTLA. "A verbal altercation occurred inside. It spilled outside, along with a large crowd.
"Emotions got out of hand," Alfred told the television station. "During the course of more people getting involved, somebody produced a handgun, fired multiple rounds and three people were hit."
The shooter, described only as a male, remained at large, KNBC reported.
"Somebody definitely knows who this was who shot these people," Alfred told the television station.