HONOLULU (AP) — A patient died and a paramedic was critically injured when their ambulance caught fire outside a hospital in Hawaii, emergency officials said.

“We had an ambulance tonight for reasons we don’t understand catch on fire, possibly explode, prior to entering the hospital,” said Dr. Jim Ireland, the emergency services director. “We’re all just very concerned about our team and the patient that lost their life.”

The 91-year-old patient and the paramedic were in the back of the ambulance as it pulled up to Adventist Castle Health in Kailua Wednesday night. Another emergency medical technician who was driving the ambulance escaped injury. The paramedic in back, an eight-year veteran, was initially treated at the hospital and then taken to another emergency room at the Straub Burn Unit, a city and county news release said.

“All our paramedics, EMTs and dispatchers are all treasured members of our staff and or family, they save lives every day, and it’s just very hard to be in a situation where our team is the ones who are injured. I’ll just leave it at that,” Ireland said. “Please pray for him.”

The Honolulu Fire Department is investigating.