All the 12 US marines onboard the two Marine Corps CH-53E Super Stallion helicopters that crashed off Oahu Island in Hawaii, have been confirmed dead.
The helicopters, each carrying six soldiers, belonged to the first Marine Aircraft Wing from the Marine Corps Air Station at Kaneohe Bay.
The collision occured just before midnight on 14 January, when the helicopters were on a routine training mission.
Neither of the aircraft were reported to have issued any distress call.
A five-day search-and-rescue operation was undertaken by the Coast Guard across 40,000nm² of the ocean, along with the navy, the National Guard, Hawaii fire and police, and Ocean Safety.
A Coast Guard helicopter crew reported spotting debris of the crashed helicopters, including an empty life raft, off the town of Haleiwa, on the north shore of Oahu, seven miles from the coast.
The 12 US marines, who were initially listed as missing, are now declared dead by military sources.
US Secretary of Defense Ash Carter said: "While there is no way to comprehend the grief their families feel today, this we do know: These proud Marines died as they lived, in service to a country they loved and in dedication to a cause greater than themselves."
Image: Two CH-53E Super Stallion helicopter aboard amphibious assault ship USS Bataan. Photo: courtesy of Mass Communication Specialist 1st Class Ken J. Riley, US Navy.