The U.S. Air Force said Saturday it has confirmed that the human remains discovered at the site of a helicopter crash in Okinawa on Monday are those of the fourth crew member.

The 18th Wing's public affairs section at U.S. Kadena Air Base said it has confirmed the death of Tech. Sgt. Mark Smith, 30, a flight engineer with the 33rd Rescue Squadron.

The HH-60 rescue helicopter Smith was aboard crashed Monday in a mountainous area within the premises of Camp Hansen, a U.S. military installation on Okinawa Island, around 2 km from the nearest residential area.

The other three crew members had been confirmed safe. The Kadena base said Tuesday that human remains had been discovered at the crash site but had yet to be identified.