NEWPORT BEACH, Calif. (AP) — A veteran lifeguard who died rescuing a struggling swimmer this weekend was overcome as big, rough waves rolled in along the Southern California coast, beachgoers said Monday.

"The waves were huge," said Shirley Reinker.

She said lifeguards were running up and down the beach Sunday telling people to enter the water no deeper than their ankles.

"They were rescuing all day, just constantly rescuing," she said.

Lifeguard Ben Carlson, 32, was pulled from the water around 8 p.m. Sunday by fellow lifeguards following a frantic, three-hour search, Newport Beach Fire Department Chief Scott Poster said. An autopsy disclosing the cause of death has not been released.

The 15-year department veteran went into the water to help a swimmer when they were hit by a large wave, Poster said. Carlson went under water, and the swimmer made it to shore safely. Searchers were hampered by up to 12-foot swells, Poster said.

"It was just an utter tragedy to lose a man of that caliber in the water today," he said, noting it was the first time a city lifeguard died in the line of duty.

"Ben was a well-respected individual, always a nice guy, always was there to help somebody," Poster said. "He'd give his shirt off his back at any time."

The National Weather Service had issued a warning Sunday of dangerous rip currents and high surf along Southern California beaches due to a swell originating in the Southern Hemisphere.

"People think it's all fun and games sitting in the lifeguard stand, soaking up the sun. But it can be very dangerous out there," said Ray Beer, who has lived along the ocean and watched the surf for 17 years.

"It's not a bathtub out there," he said.

Los Angeles County firefighters rescued a 25-year-old man who was caught in the waves off Rancho Palos Verdes and high tide breached a sand berm in Long Beach.

The lifeguard's death came a day after a long-distance swimmer was bitten by a shark off Manhattan Beach.

Authorities and witnesses said the 7-foot-long juvenile had been trying to free itself from a fisherman's hook when it lunged at Steven Robles' chest.

The beaches remained open, but police prohibited fishing from the Manhattan Beach pier where the fisherman hooked the shark until Tuesday.