A U.S. Air Force Osprey aircraft crashed into the ocean Wednesday near the small southern Japanese island of Yakushima with eight people onboard, killing at least one crew member, a U.S. defense official confirmed to CBS News. An official with Japan's coast guard told CBS News that one crew member was recovered dead and search operations were continuing into the night for the others from the Osprey.

The official told CBS News that two helicopters and six boats were involved in the search operation. U.S. Air Force Special Operations Command said in a statement the Osprey was performing a routine training mission.

Coast guard spokesperson Kazuo Ogawa was quoted earlier by the Agence France-Presse news agency as saying an emergency call came in from a fishing boat to report the crash. He said there were eight people on the Osprey, a figure that the coast guard later revised to six before the U.S. defense official said that eight airmen were onboard.

Japanese national broadcaster NHK aired video from a helicopter showing a coast guard vessel at the site with one bright orange inflatable life raft seen on the water, but nobody in it.

NHK said an eyewitness reported seeing the aircraft's left engine on fire before it went down about 600 miles southwest of Tokyo, off the east coast of Yakushima.

The Kagoshima regional government said later that the Osprey had been flying alongside another aircraft of the same type, which landed safely on Yakushima island.

Japan's Kyodo News cited coast guard officials as saying the first emergency call came in around 2:45 p.m. local time (12:45 a.m. Eastern), and it said the Japanese Defense Ministry reported the Osprey dropping off radar screens about five minutes before that.

An Osprey can take off and land vertically like a helicopter but then change the angle of its twin rotors to fly as a turbo prop plane once airborne.

The Japanese government approved last year a new $8.6 billion, five-year host-nation support budget to cover the cost of hosting American troops in the country, reflecting a growing emphasis on integration between the two countries' forces and a focus on joint response and deterrence amid rising threats from China, North Korea and Russia.

The Osprey involved in the crash was assigned to Yokota Air Force Base outside Tokyo, Air Force Special Operations Command said. NHK reported the aircraft had departed Wednesday from a smaller U.S. air station in Iwakuni to fly to Kadena Air Base on Okinawa, which is in the same island chain as the tiny island of Yakushima. The small island sits just south of Kagushima prefecture, on Japan's main southern island of Kyushu.

The U.S. military's Kadena Air Base is the most important and largest American base in the region.

There have been a spate of fatal U.S. Osprey crashes in recent years, most recently an aircraft that went down during a multinational training exercise on an Australian island in August, killing three U.S. Marines and leaving eight others hospitalized. All five U.S. Marines onboard another Osprey died the previous summer when the aircraft crashed in the California desert.

An Osprey crashed in shallow water just off the Japanese island of Okinawa in 2016, but all the U.S. Marines onboard survived that incident. 

CBS News' Elizabeth Palmer and Lucy Craft in Tokyo and Eleanor Watson at the Pentagon contributed to this report.

In:
• Plane Crash
• China
• Asia
• Japan

Tucker Reals

Tucker Reals is cbsnews.com's foreign editor, based in the CBS News London bureau. He has worked for CBS News since 2006, prior to which he worked for The Associated Press in Washington D.C. and London.