SAN DIEGO (AP) — A swimmer was seriously injured in a shark attack on the Southern California coast Sunday, prompting temporary beach closures, authorities said.

The attack happened Sunday morning at Del Mar City Beach in Del Mar, about 20 miles (32 kilometers) north of San Diego, local officials said.

The 46-year-old man, an ocean swimmer who regularly trains at the beach, suffered significant but not life-threatening injuries. He was taken to a hospital for treatment, city officials said.

The attack happened about 100 yards (91 meters) from a beach lifeguard station. The swimmer was bitten in the torso, left arm and hand.

Authorities said the beach will remain closed for surfers and swimmers until Tuesday morning.

The man was attacked when he was swimming with roughly a dozen other people, said Chief Lifeguard and Community Services Director Jonathan Edelbrock. Lifeguards were setting up on the beach for the day when they were alerted of the situation.

No one had seen the shark when the attack happened, Edelbrock said. The city also deployed a drone and a boat to look for the shark afterwards with no success.

“The water visibility was really poor,” he said. “You just can’t see anything that’s moving through the water column at all. The exact moment of the incident was really the only interaction with, or sighting of, the shark.”

Another swimmer was attacked by a shark in November 2022 on the coast of Del Mar, where she was bitten in the upper thigh. A popular beach in San Clemente, 41 miles (66 kilometers) north of Del Mar, also closed for the Memorial Day holiday last week after a shark bumped a surfer off his board.