TAIPEI (Taiwan News) — Four Navy officers were injured when their S-70C anti-submarine helicopter crashed during training at their base in Kaohsiung City Wednesday (June 22) afternoon.

The aircraft came in for a hard landing on a runway at the Zuoying Naval Base, according to the military. A CNA report said the helicopter immediately caught fire, with some of the four crew members sustaining life-threatening burns.

The injured were moved to the nearby Zuoying branch of the Kaohsiung Armed Forces General Hospital, where a technician was still in critical condition Wednesday evening with burns over 95% of his body. The pilot and co-pilot had escaped with only slight injuries, while a third crew member suffered second-degree to third-degree burns over 10% of his body.

Parts of the helicopter knocked a 20-centimeter-wide hole in the metal garage door of a private home in the area, according to media reports. Police cordoned off the building after a helicopter part had been found inside, per CNA.

The Navy ordered all Sikorsky-made helicopters of the same type to be grounded for a thorough examination, and a special task force will investigate the cause of Wednesday’s crash.