Confirmation of the cause of death was pending an autopsy. Dietz said he can't confirm whether the man was a swimmer who was pulled from the water and given CPR.
Twelve other people, including a 15-year-old boy, were examined after the strike on the beach, in the water and on the famed Venice Beach boardwalk. Los Angeles fire spokeswoman Katherine Main said they had effects ranging from anxiety to needing CPR, although not all may actually have been struck. Nine went to hospitals.
Steve Christensen said his friend had been body-surfing and was sitting on the beach when lifeguards began searching for a missing swimmer.
"He (Christensen's friend) went out to the water to find him and walked right into him," Christensen said. "He was face down on the bottom."
Christensen said his friend pulled the man, who appeared to be in his 20s, from the water, and lifeguards began CPR before taking him away on a truck.
"The guy wasn't moving. He wasn't responding at all," Jesus Zamudio of Riverside told the Los Angeles Times (http://lat.ms/UvUQgs).
Stuart Acher said he was struck by lightning while playing volleyball on the beach.
"We went about our game and then all of a sudden, there was a big flash of light and a boom, and it felt like someone punched me in the back of my head," he told KABC-TV. "It went down my whole side of my right body, and my calves sort of locked up, and I fell over. And I looked up and everybody else was, you know, falling over."
Paramedics examined Acher but he felt all right and went back to playing volleyball.
"The majority of the folks that were on the (volleyball) court all felt a little tingly," said another player, Jerome Williams. "Everyone hit the court. It sounded like a sonic boom."
On Santa Catalina Island, often called Catalina Island, off the coast, a 57-year-old man was struck by lightning on a golf course and was hospitalized in stable condition, said Steve Denning, a law enforcement technician with the Los Angeles County Sheriff's Department. He did not have other details.
The lightning strikes occurred as a fierce but brief thunderstorm hit the island, causing minor flooding and setting two small fires in the brushy backcountry that were quickly doused, Denning said.
Parts of the island received more than three-quarters of an inch of rain in about two hours, said Stuart Seto, a weather specialist with the National Weather Service in Oxnard.
A moisture-laden monsoonal flow usually spawns thunderstorms when it hits hot weather in the deserts and sometimes in the mountains this time of year, Seto said.
"This time, it came all around San Diego and northwards," spreading out into the ocean as well as inland, Seto said.
The storms began to dissipate as they moved northwest, leaving just a chance of storms through Monday, mainly in the deserts and mountains.