One person has died, and seven are missing Sunday following an accident in which two military helicopters collided before crashing into the sea.

A spokeswoman for Japan's Self-Defense Force (SDF) confirmed the late Saturday incident to AFP, saying one person was rescued but subsequently confirmed dead.

PHOTO | COURTESY a helicopter

Defence Minister Minoru Kihara stated that rescuers "spotted what are believed to be parts of the aircraft in the sea, and we believe the two helicopters crashed."

"At this point the cause is unknown, but firstly we do our best to save lives," Kihara told reporters.

Hours later, Kihara informed reporters that the crew member who had been recovered "was confirmed dead."

PHOTO | COURTESY Rescue efforts 

He also stated that the ministry "discovered the flight recorders in places close to each other," and that the "possibility is high that (the two helicopters) collided."

According to authorities, the helicopters crashed while training to fight submarines at night off the Pacific Ocean's Izu Islands.

The Maritime Self-Defense Force's (MSDF) chief of staff, Ryo Sakai, told reporters that "the flight recorders are being analysed" as officials interrogate the crew of a third helicopter that was participating in the training but was not involved in the accident.