Bambang Sulistio, an air force spokesman, said an investigation was under way, but that it was too early to discuss the possible causes of the crash.

"Before we fly there are procedures and checks to make sure the plane is in good condition," he said.

"We're setting up an investigation team to see if there was human error or aircraft failure. From our information, it crashed, there was some sort of explosion and it caught fire."

Accidents are not uncommon to the Indonesian military's fleet of ageing aircraft.