The captain of a 37-foot fishing boat was missing after it ran aground on Ocean Beach in San Francisco early Monday, officials said.
A search for the captain, Timothy Lybrand, began when the fishing vessel Paloma was reported washed onto the beach near Seal Rock around 3:30 a.m., according to the U.S. Coast Guard.
After eight hours, the Coast Guard suspended its search effort for the missing captain.
Coast Guard and San Francisco Fire Department crews searched an 18-square-mile area spanning from Ocean Beach to the Golden Gate bridge from about 4 a.m. until noon, but did not find Lybrand.
Capt. Mike Day, deputy commander of the Coast Guard's San Francisco sector, said efforts had been suspended "given the close proximity to shore, and the vessel operator's stated intention to abandon the vessel, as well as the extensive search effort".
It is still unclear how far the boat was from shore when Lybrand may have abandoned it.
The captain had said in a communication with another fishing vessel before his boat ran aground that he might try to swim to shore, but it's unclear why he said that or how far from shore he was at the time, according to the Coast Guard, which is investigating the incident.
The Paloma has a 400-gallon fuel tank, but no visible sheen from the fuel was reported.
"We're ensuring all the fuel is properly removed prior to getting the boat out of there to ensure there's no harm to the environment," Coast Guard Lt. Sean Kelly said.
Chilly ocean waters added a sense of urgency to the search effort.
"With the water temperature as cold as it is, it plays a factor in finding someone as quickly as possible," Kelly said.