A U.S. Marine Corps Osprey was undamaged and no crew members were injured after the tilt-rotor aircraft made an emergency landing Saturday at Amami airport in Kagoshima Prefecture, a Japanese government source said.

The U.S. military explained it was a preventive landing to avoid an accident, the source said. The emergency landing took place on Amami Island shortly before 9 p.m. Saturday while the aircraft was conducting routine training.

According to the Defense Ministry's Okinawa Defense Bureau, the transport aircraft belongs to U.S. Marine Corps Air Station Futenma in Okinawa, which is home to the bulk of U.S. military facilities in Japan.

The local fire department did not dispatch firefighters because there was no call for assistance.

Another Osprey made an emergency landing Tuesday at a U.S. airfield on Ie Island in Okinawa, while another made a crash landing off Okinawa's main island last December.

The incidents involving the Osprey, which lands and takes off like a helicopter but can cruise like an airplane, have heightened the concerns that many residents have about their checkered safety record.