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LOS ANGELES, April 29 (Reuters) - At least three sailors were killed and one was missing after a yacht racing from California to Mexico apparently collided with a much larger ship, officials said on Sunday.
The Coast Guard said a helicopter joined the search for the fourth sailor an hour after dawn on Sunday.
"Right now, we're continuing our search and trying to find the person," said Coast Guard spokesman Petty Officer 3rd Class Seth Johnson.
It was the third racing major accident in the waters off California in recent weeks, and the second to result in fatalities.
The Newport Ocean Sailing Association said the 37-foot (11.3-meter) Aegean disappeared off their online tracking system early on Saturday while it was sailing several miles off the coast near the border of Mexico and California.
A Coast Guard cutter combed the waters for wreckage and the missing fourth sailor through the night, Johnson said.
The association said none of the bodies had been identified.
"An investigation was continuing, but it appeared the damage was not inflicted by an explosion but by a collision with a ship much larger than the 37-foot vessel," it said in a statement.
The race began in Newport Beach on Friday and the last sailboats were due to arrive in Ensenada on Sunday.
The accident in the southern California waters follows two others in recent weeks off the northern California coast, which prompted the U.S. Coast Guard on Thursday to suspend sailboat racing in the Pacific Ocean around San Francisco.
In the first of two recent accidents, a pair of crew members from an Australian yacht on a round-the-world race were injured off Northern California when a massive wave struck the ship on March 31.
In the April 14 fatal accident, a series of powerful waves pummeled the 38-foot (11.6-meter) yacht Low Speed Chase during the Full Crew Farallones Race, sweeping crew members overboard and tossing the vessel onto a rocky island.