The US Coast Guard has called off its search on Wednesday for people missing from a triple-deck pontoon boat that capsized in San Francisco Bay a day earlier, leaving the casualty toll at one confirmed death and three others lost at sea.
The vessel with about 20 people aboard rolled over and sank near Alcatraz Island on Tuesday after being struck by a large wave, according to Coast Guard and San Francisco Fire Department officials.
Good Samaritans in other vessels nearby, including a couple of fishermen, rushed to the scene and rescued many of the people who were clinging to the side of the sinking boat before emergency response teams arrived.
One victim was confirmed dead at the scene, while divers and other rescue personnel from the fire department and Coast Guard launched a search for three missing passengers, officials said.
The Coast Guard said it was calling off the search at around sunset on Wednesday, after hopes of finding survivors in the frigid waters vanished, leaving the three who were still missing presumed dead.
Authorities did not publicly identify the victims, but local television station KPIX-TV, a CBS-owned station, reported that the person pronounced dead was the boat captain's brother, and that the three others were the captain's sister, his sister-in-law, and a friend.
A Coast Guard official told reporters on Wednesday that some of the passengers were below deck when the vessel was struck sideways by a wave and overturned, likely trapping some people inside the sinking boat.

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