ANCHORAGE, Alaska (AP) _ Federal investigators are looking into what appears to be poaching and mutilation of walruses for ivory in the Bering Sea.

Officials first learned of the kills Tuesday after Coast Guard safety inspectors boarded a fishing boat that recently had returned to port from the Bering Sea herring fishery. They found two walrus skulls and two sets of tusks aboard.

''They were in the process of cleaning them out, boiling them,'' said Coast Guard Chief Petty Officer Ed Moore.

The evidence has been turned over to the U.S. Fish and Wildlife Service.

A second seizure of walrus remains was reported Wednesday by a Coast Guard boarding group after a safety inspection of the fishing vessel Maverick.

Both seizures were made at Naknek, a port city about 300 miles southwest of Anchorage, where the Coast Guard had set up a temporary safety inspection detachment.

According to the Coast Guard, Maverick skipper Delton Repnow said walrus parts were retrieved after they were found floating in the water.

And Steven J. Hansen, the skipper of the first vessel, the tender Chichigoff, told investigators that on June 4 his vessel found a dozen walrus carcasses floating about 40 miles south of Nome in Norton Sound.

Ten walrus carcasses were headless and two still had their heads, said Walter E. Soroka, a fish and wildlife field supervisor.

In the process of cleaning the heads and removing the tusks, the crewmen found at least one small-caliber bullet in one of the walruses, officials said.

Crew members told the Coast Guard they thought they legally could keep the walrus ivory and had intended to report their find as required by law. The Coast Guard said discovery of the carcasses had been entered in the vessel's log book.

The Marine Mammal Protection Act makes it a federal crime to recover ivory from walruses found at sea, Soroka said. It is legal to recover walrus carcasses found on shorelines.

Eskimos and other Alaska natives are allowed to hunt walruses for subsistence use, but cutting off walrus heads and leaving the rest of the carcass is illegal, even for natives, said Soroka.

''We don't know who removed the heads,'' he said. ''We plan to find out. That's something that we look at seriously.''

Soroka said Hansen has cooperated in the investigation. ''He contacted me. ... He told me he misconstrued the laws,'' Soroka said.

Robert Brophy, president of Seattle-based Icicle Seafoods Inc., the owner of the vessel, said he doubted his employees intentionally broke the law.

Walrus ivory is used in Alaska and around the world as a craft substitute for elephant ivory. With the recent crackdown on illegal elephant hunting in Africa, Alaska ivory has become more popular among carvers.

Penalties for poaching are strict. If the crew of a fishing vessel is found to have been poaching walruses, the government may seize the vessel, Soroka said. Individuals convicted of violating the Marine Mammal Protection Act face up to a year in prison and $100,000 fine.