By Patrick Mondout
On December 4, 1977, a Malaysian Airlines System (MAS) 737 was hijacked en route between Penang and Kuala Lumpur. Witnesses saw the aircraft descend from an altitude of 21,000 feet to a few thousand feet before leveling off. The aircraft then plunged into a swamp 30 miles southwest of Johor Baharu, Malaysia. All 93 passengers and 7 crew were killed.
Investigators later determined that both pilots must have been shot.
Source: National Transportation Safety Board (NTSB) report.