SAN FRANCISCO (CBS SF) – The U.S. Coast Guard suspended its search Monday for a man who was lost in the Bay on Sunday afternoon after his kayak overturned near San Francisco’s Pier 80.

Thomas Gregoire, 56, was kayaking with a friend when his kayak flipped over. The incident was reported around 2:40 p.m. by a professional mariner who was mooring a motorboat in the area, according to the Coast Guard.

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Gregoire apparently got too close to a tugboat that was repositioning a barge and got caught in the boat’s wash, San Francisco police spokesman Officer Carlos Manfredi said.

He was wearing a red shirt and blue vest when he entered the water, authorities said.

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The Coast Guard and police searched the Bay for about 18 hours for Gregoire before calling off the search shortly before 9:30 a.m. Monday.

Authorities said that because of the time that has lapsed since he went into the water, it is unlikely that Gregoire is still alive.

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