BOSTON — The Coast Guard requests assistance Tuesday to identify a mariner who made a distress call Monday night in Blue Hill Bay, Maine, west of Mount Desert Island, according to a press release.

Coast Guard Sector Northern New England in Portland received a call over VHF-channel 16 at 7:43 p.m. Monday from an unidentified male communicating his position, but not the nature of the distress or the name of the vessel, the Coast Guard said in the release.

A 47-foot Motor Life Boat was launched from Coast Guard Station Southwest Harbor and searched throughout the night for any vessels in distress, the release said. The crew has been relieved by a 25-foot Response Boat-small.

Severe fog has hampered search efforts, with visibility reduced to 10 feet or less throughout the night, the release said.

The Coast Guard asks that anyone who can identify the caller or has additional information contact the Sector Northern New England Command Center at 767-0303.