A lobsterman who died Friday while fishing near Marshall Island in Jericho Bay off Stonington may have drowned, the Coast Guard said.

Wayne “Butch” Ciomei, 59, was found in the water wrapped in a fishing line and his 36-foot lobster boat, the Chelsea Lynn, out of Stongington, was aground and running.

Ciomei’s son alerted the Maine Marine Patrol about 4:30 p.m. Friday that his father was long overdue in returning from a fishing trip. The marine patrol called in the Coast Guard, said Chellsey Phillips, a Coast Guard public affairs officer.

The Coast Guard issued a call to other boaters for help and sent a 47-foot rescue boat to the scene.

The son of the missing fisherman found Ciomei and his boat about 5:30 p.m.

The cause of the accident and the official cause of death are both still under investigation, Phillips said.

The Coast Guard advised boaters and fishermen that the ocean remains frigid, Phillips said.

This story has been updated to correct Ciomei’s age and to note the cause of death is still under investigation.