A US Navy aircraft carrying 11 crew and passengers crashed into the ocean southeast of Okinawa on Wednesday afternoon, the Seventh Fleet said.
The aircraft was traveling to the USS Ronald Reagan aircraft carrier, which is currently operating in the Philippine Sea, when it crashed.
The cause of the crash is not known, the Seventh Fleet, based in the Japanese port of Yokosuka, said in a statement.
The Reagan crew is conducting search and rescue operations and trying to recover the crew.
The names of the crew and passengers are being withheld while next of kin are notified.