A Japanese military helicopter crashed in southwestern Japan on Monday, ripping the top floor off a house and setting the building on fire, officials said.
The two crewmembers who were aboard died after suffering heart and lung failure, according to Japanese military officials.
The Boeing AH-64 combat helicopter crashed in Kanzaki city in Saga prefecture, defense officials said.
Public broadcaster NHK showed orange flames and black smoke rising from the charred house, which had its upper floor torn off. Witnesses reported a big boom and ripping noises coming from the sky before the crash.
The four residents of the damaged house were believed to have been away at the time of the accident, Masaki Endo, a disaster official at the Saga prefectural government, told the Associated Press. No one else on the ground was believed to have been hurt, he added.
The helicopter fell nose down after losing contact with air traffic control and the cause of the accident is under investigation.
Prime Minister Shinzo Abe ordered the grounding of all 12 helicopters of the same type for safety checks, Kyodo News agency reported.
The crash follows a series of emergency landings and other incidents involving U.S. military aircraft on Japan's southern island of Okinawa.
The Associated Press contributed to this report.