A Hawaiian tuna longliner vessel caught fire Tuesday afternoon off Oahu, but its crew of six and a NOAA observer escaped uninjured in a life raft, Coast Guard officials said.

The 46-foot, 36-ton Miss Emma, a locally well known vessel built in 1977 and based at Honolulu, caught fire about 8 miles south of Sand Island. The crew transmitted a mayday call at 4:29 p.m., according to an account issued by the Coast Guard in Honolulu.

The Miss Emma fished out of Honolulu. Western & Central Pacific Fisheries Commission photo

A 45-foot response boat from Coast Guard Station Honolulu was first on the scene, and rescued the crew and observer, who had abandoned ship using the Miss Emma’s life raft. They were returned safely to the Miss Emma’s home port at Pier 38 in Honolulu.

Meanwhile, the crew of the 154-foot Coast Guard cutter Joseph Gerczak recovered the life raft, and stayed on station throughout the night to make sure the burning boat did not pose a danger to local maritime traffic.

Salvors came to the scene overnight as the fire burned on, and began fighting the flames Wednesday morning with the aim of salvaging the Miss Emma. But the boat sank at 7:22 a.m. in 2,700 feet of water, seven miles south of Barbers Point, Coast Guard officials said.

At sunrise a Coast Guard Auxiliary air overflight carrying a pollution responder surveyed the area, but observed no evidence of pollution or debris. The Miss Emma had fuel tankage for up to 3,200 gallons of diesel, with about 1,500 gallons on board for its last trip. Most of the fuel was likely consumed in the fire, according to the Coast Guard.