Searchers found a “debris field” off the coast of Nantucket, Massachusetts, from an air ambulance that was carrying six people when it vanished over the Atlantic on Saturday during a flight from Bermuda to Boston, the U.S. Coast Guard said.

Four Canadians and two Bermudian nationals were aboard, and their next of kin were notified as the search continued, the Coast Guard said in a statement. It added that one of its cutters would keep searching the water overnight and into Sunday.