FREMONT (CBS SF) — Emergency crews have rescued a man Tuesday evening and are searching in the dark for second victim whose kayak capsized off the coast of Fremont, according to a fire chief with the Menlo Park Fire Protection District.

One victim was in a raft and the other was in a kayak in the water south of the Dumbarton railroad trestle Tuesday afternoon when the kayak capsized.

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The man in the raft used a cellphone to call for help at 4:38 p.m., telling dispatchers that the victim who had been in the canoe was in the water with no life vest.

The Coast Guard identified the missing man as 32-year-old Kenneth Maldonado of San Jose.

An airboat was deployed, and it rescued the man in the raft within 20 to 30 minutes. The victim in the water was still unaccounted for at sunset.

“We hope it’s going to end well, but any time nightfall hits when you’ve got someone in the water with no floatation, it’s hard to say,” Fire Chief Harold Schapelhouman said. “We hope for the best.”

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Aircraft were deployed by the U.S. Coast Guard and the California Highway Patrol. Menlo Park firefighters and the Fremont Fire Department have both used drones to search the shoreline.

Firefighters from Redwood City, San Jose, Santa Clara, Fremont and Alameda County have all sent water rescue assets — and a total of six boats are currently engaged in the search, according to Schapelhouman.

Rescuers are using FLIR (Forward Looking Infrared) technology, which can pick up a heat signature – but the victim has been in the water for more than an hour and may have gotten cold.

“Best case scenario, maybe he was able to swim to shore and he’s sitting someplace where we can’t see him,” Schapelhouman said. “It’s a big bay out there.”

Firefighters suspended the search around 10 p.m., but the Coast Guard was planning to continue the search for the man late Tuesday night.

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