Three American crewmen were presumed dead on Thursday following a fire in a small tanker that ran aground in Cook Inlet on Wednesday 75 miles southwest of here, the Coast Guard said.

"The three missing crewmen were last seen trying to fight the fire in the engine room," said Lt. Geoff Merrell. They are presumed to have perished. The fourth crewman was rescued by a civilian helicopter soon after the fire began."The vessel, the 113-foot Alaska Constructor, continued to burn and was expected to burn out on Thursday morning, said Merrell at the Coast Guard Operations Center in Juneau.