The AT-3 aircraft took off on a routine training mission from the air force academy in Kangshan, southern Taiwan, at 2:14 pm (0614 GMT) but lost contact with controllers about 30 minutes later, the air force said.

Rescuers have been mobilized to search for the two pilots -- air force Major Tuan Lien-sheng and trainee Second-Lieutenant Chiu Yi-feng, it said.

The air force immediately grounded some 50 AT-3s for a thorough check as the cause of the accident was pending investigation.

An air force jet fighter crashed April 29 into a mountain, with the two pilots on board parachuting to safety.

WAR.WIRE