Search and rescue efforts continue on Sunday, four days after a US Osprey military aircraft crashed into the sea off Yakushima Island in the southwestern Japanese prefecture of Kagoshima.

Eight personnel were on board when the Osprey went down on Wednesday. One of them has been confirmed dead, while seven others remain unaccounted for.

The US Air Force says the crewmember confirmed dead has been identified as 24-year-old Staff Sergeant Jacob Galliher, who was stationed at Kadena Air Base in Okinawa.

What appears to be part of the wreckage of the aircraft was retrieved by fishers in waters off the island and stored in a warehouse in the town of Yakushima.

On Sunday morning, US personnel were seen visiting the warehouse, wrapping up the stored items and loading them onto a truck before heading to Yakushima Airport.

The US Air Force also said the nuclear-powered aircraft carrier USS Carl Vinson is taking part in the search for the missing crewmembers. Carrier-based aircraft and drones as well as divers are being used in the operation.

The Air Force says in a statement, "Our joint force and Japanese allies stand united in our determination to bring our air commandos home."

Meanwhile, as part of the search operation, two US Ospreys arrived at the airport on Amami Island in Kagoshima Prefecture on Sunday morning.
The regional bureau of Japan's Defense Ministry says those Ospreys are deployed at US Marine Corps Air Station Futenma.

The two Ospreys took off at around 10:50 a.m., after spending about an hour and 20 minutes at the airport, then headed eastward.