US authorities have located debris believed to be from a medical transport aircraft that went missing while carrying six people from Bermuda to Boston, Massachusetts.

The Federal Aviation Administration (FAA) said it lost contact with the Gulfstream G-100 shortly after 1:00 a.m. local time on Saturday, as the aircraft was travelling towards Boston.

The US Coast Guard said a search for survivors was continuing off the coast of Nantucket, a Massachusetts island.

Authorities have notified the next of kin of all six people on board, comprising four Canadian nationals and two Bermudian nationals.

In an update on Saturday night, the Coast Guard said search crews had located a debris field confirmed to be from the missing aircraft.

«“Search crews located a debris field confirmed to be from the aircraft off the coast of Nantucket,” the Coast Guard said.»

Ships, helicopters and aircraft were deployed in the search, with operations continuing through the night.

Aircraft loses communication

According to flight data from FlightAware, the aircraft departed Bermuda’s L.F. Wade International Airport at about 11:40 p.m. local time and was scheduled to arrive at Boston’s Logan International Airport at approximately 1:30 a.m. EDT.

The aircraft’s tail number, released by the Coast Guard, indicates that it was operated by Latitude Air Ambulances, a company that provides international medical transportation for patients returning home.

Clarence Togeretz, the company’s director of flight operations, told CBC News that the aircraft had two pilots and two medical staff, all Canadian nationals.

The crew had travelled to Bermuda to pick up a patient and the patient’s relative, who were not Canadian, he said.

FlightAware data showed that the aircraft experienced a significant drop in altitude before communications were lost, descending from about 7,300 metres (24,000 feet) to 3,300 metres (11,000 feet).

Pilot reportedly declared emergency

Radio transmissions also indicated that the aircraft was experiencing communication difficulties shortly before it disappeared from radar.

According to the Boston Globe, based on transmissions obtained from LiveATC.net, an air traffic controller asked the pilot whether the aircraft was “coming in blind” and whether an emergency was being declared.

The pilot’s response was reportedly inaudible.

The controller later said the pilot’s transmission was too weak to understand and subsequently confirmed that the pilot had declared an emergency.

An area fire dispatcher reportedly instructed emergency crews shortly after 1:00 a.m. EDT to prepare for an aircraft experiencing an “electrical issue.”

The dispatcher later reported that the aircraft had lost both radio and radar contact.

The Coast Guard has said it will provide a further update on the search operation on Sunday morning local time.