The U.S. Coast Guard is searching for two missing fishermen whose boat sank off the coast of Nantucket after confirming the rescue of two other members of its crew.

The Misty Blue, a 69-foot vessel out of New Bedford, Massachusetts, issued a distress call shortly after 6 p.m. Monday, according to the Coast Guard. Four people were reportedly aboard the ship, which sank approximately 10 miles south of Nantucket.

Two Coast Guard aircraft and multiple ships were diverted to search for the Misty Blue. Two members of its crew were rescued by good Samaritans aboard the Enterprise, a ship that was passing.

The rescued fishermen were transferred to the Coast Guard Cutter Steelhead. Their conditions were not immediately clear.

The fishing boat and the other two crew members have not been found. Coast Guard officials said after 8:30 p.m. they were continuing to search by air and by ship.

No further information was immediately available.