ANCHORAGE, Alaska (AP) — Bobbing for days atop a capsized skiff in Alaska’s frigid Bering Sea, a 15-year-old boy held on until he was rescued by a fishing vessel this week, the U.S. Coast Guard said.

The boy's brother and a cousin died sometime after the small boat flipped, according to the rescuers.

Their bodies were found after the teen was hoisted to safety near St. Lawrence Island — a remote Alaskan island that’s closer to Russia than it is to the United States.

The captain of the fishing boat, The Northwest Explorer, said the boy had clung to the skiff for close to three days. “That’s one tough kid,” Adam White told KTUU-TV in Anchorage.

Coast Guard planes and helicopters began searching for the skiff Monday morning after family members reported the three missing the night before. Authorities did not release the names of the three.

The group left St. Lawrence Island on Friday and planned to return early Sunday, the Coast Guard said.

The Coast Guard said one of its air crews spotted the boy Monday morning and deployed a raft and supplies before contacting The Northwest Explorer.

Video of the rescue shows the boy in a bright yellow jacket kneeling atop the overturned skiff. The boat's crew tosses the boy a line, tugging the skiff closer until they can pull him into a rescue basket.

The boy was experiencing symptoms of hypothermia when he got onto the boat, the Coast Guard said.

The fishing boat crew warmed him with blankets and hot packs, its captain said.

“Through the teeth chattering, he had mentioned that his brother was still under the skiff,” White said. “And then he said that, in the previous night, before our rescue, that his cousin had slipped away.”