On the evening of 4 December 1977, the Boeing 737-200 aircraft flying the service crashed at Tanjung Kupang, Johor, Malaysia, while purportedly being diverted by hijackers to Singapore.

[7] Captain GK Ganjoor and First Officer Karamuzaman Jali were making landing preparations at 19:54, while at an altitude of 4,000 feet (1,200 m) over Batu Arang and descending toward Runway 33 at Subang Airport, when the crew reported to Subang Tower that an "unidentified hijacker" was on board, after someone knocked on the cockpit doors.

"[10] In the last few minutes of the tapes from the cockpit voice recorder, investigators heard conversation between the pilots and the hijackers about how the aircraft would run out of fuel before it could make it to Singapore, followed by a series of gunshots.

They concluded that both the pilot and co-pilot were fatally shot by the hijacker, which left the plane "professionally uncontrolled".

[12] At 20:36, the residents of Kampong Ladang, Tanjung Kupang in Johor reported hearing explosions and seeing burning wreckage in a swamp.