Floating wreckage that could be aircraft parts has been spotted during a search and rescue operation for the missing Japanese Ground Self-Defense Force (GSDF) helicopter carrying 10 people, including a lieutenant general,

The four-blade, twin-engine UH60 helicopter, known as the Black Hawk, vanished from radar screens near Okinawa's Miyakojima Island, at about 3.55 p.m. on Thursday shortly after taking off to survey nearby land features, the military said.

Addressing a press conference, General Yasunori Morishita, chief of staff of the GSDF, said the multipurpose chopper which belongs to a unit under the GSDF's 8th Division based in Kumamoto prefecture is believed to have been caught up in an aircraft accident, reports Xinhua news agency.

Two pilots, two mechanics, and six crew were on board and all were SDF members, whose whereabouts still remain unknown, including Lieutenant General Yuichi Sakamoto, the 55-year-old head of the division, Morishita confirmed.

Oil and objects including what could be part of a rotor blade were found in the sea area where the accident is believed to have occurred, according to the Japan Coast Guard who dispatched patrol ships to nearby waters in search for the helicopter.

A lifeboat printed with GSDF signs was also found in a folded state, carrying no one on it, it added.

The GSDF is trying to confirm whether the objects are from the missing helicopter.

"We are putting maximum priority on human life and rescue operations," Prime Minister Fumio Kishida told reporters in Tokyo.

Rough weather conditions were not reported around the time the helicopter went missing.