The Yak-130 jet took off at 9:55 a.m. at Phu Cat airport for a training exercise, according to the Ministry of National Defence.

At 10:38 a.m. when the aircraft was supposed to finish its training session, the pilots reported that the plane could not release the gear. They tried to take responsive measures to handle the situation but did not succeed.

The pilots reported the incident to the flight commander and were ordered to parachute, Xinhua news agency reported quoting Vietnam News Agency.

Officials are currently working to locate the crash site and search for the missing airmen.