(CNN) -- Coast Guard and Air National Guard crews spent a second day in search of four sailors from a yacht that ran aground off San Francisco over the weekend, the services said Sunday.
At least one person died and three were rescued from the "Low Speed Chase," Petty Officer 2nd Class Levi Read said. But the remaining four people aboard remained unaccounted for Sunday afternoon, and rescuers were searching a 15-by-30-mile patch of the Pacific Ocean in hopes of finding them alive.
The 38-foot sailboat was taking part in a race around the Farallon Islands, 28 miles west of the Golden Gate Bridge. The vessel's skipper reported that the yacht was hit by a series of large waves that rolled it over, tossing several crew members overboard and running it aground, the Coast Guard said Sunday.
The search effort included three helicopters, a C-130 transport and four Coast Guard vessels, including the cutters Aspen, Pike and Sockeye.
The yacht was taking part in the Full Crew Farallon Race, a contest that dates to 1907, according to the San Francisco Yacht Club. In a statement on its website, the club said "Low Speed Chase" was one of its vessels and that it was awaiting news of the rescue effort.
Late last month, the Coast Guard rescued racers taking part in an around-the-world contest when a giant wave damaged their yacht off the coast of San Francisco. The Geraldton Western Australia was on the sixth leg of an eight-leg, 11-month race when it was struck March 31.