ANCHORAGE, Alaska -- The Coast Guard says four crew members are dead and one person is still missing from a Seattle-based fishing vessel that began sinking off Alaska's Dutch Harbor.

Coast Guard Lt. Eric Eggan said 42 other crew members who abandoned ship early Sunday have been recovered safely.

The Alaska Ranger started taking on water shortly before 3 a.m. Sunday after losing control of its rudder, reported the Coast Guard. The boat is sinking about 120 miles west of Dutch Harbor, Alaska.

The Coast Guard said earlier in the day that all 47 crew members abandoned ship and were in life rafts awaiting rescue, but now they confirm four are dead.

Eggan said it’s unknown how or when the four died. The identities of the dead are also unknown.

Those on board the Alaska Ranger were heading to Dutch Harbor in a Coast Guard cutter and the sinking vessel's sister ship, the Alaska Warrior. The vessel took part in the rescue operation along with two Coast Guard helicopters that were used to pluck crew members from life rafts, Chief Petty Officer Barry Lane.

State environmental regulators were notified that the ship was carrying 100,000 gallons of diesel, according to Leslie Pearson, emergency response manager for the Alaska Department of Environmental Conservation. A Coast Guard c-130 crew reported an oil sheen that covered an area of a quarter mile by a half mile, Coast Guard spokesman Ray Dwyer said.

The Alaska Ranger is owned by Seattle-based Fishing Company of Alaska.