General Zia-ul-Haq died in a plane crash on 17 August 1988. After witnessing a US M1 Abrams tank demonstration in Bahawalpur, Zia had left the small town in the Punjab province by C-130 Hercules aircraft. Shortly after a smooth take-off, the control tower lost contact with the aircraft. Witnesses who saw the plane in the air afterward claim it was flying erratically, then nosedived and exploded on impact. In addition to Zia, 31 others died in the plane crash, including Chairman Joint Chiefs of Staff Committee General Akhtar Abdur Rehman, close associate of General Zia Brigadier Siddique Salik, the American Ambassador to Pakistan Arnold Raphel and General Herbert M. Wassom, the head of the U.S. Military aid mission to Pakistan.[22][23] Ghulam Ishaq Khan, the Senate Chairman announced Zia's death on radio and TV. The manner of his death has given rise to many conspiracy theories.[24] There is speculation that America, India, the Soviet Union (as retaliation for US-Pakistani supported attacks in Afghanistan) or an alliance of them and internal groups were behind the attack.[25][26]
A board of inquiry was set up to investigate the crash. It concluded the most probable cause of the crash was a criminal act of sabotage perpetrated in the aircraft. It also suggested that poisonous gases were released which incapacitated the passengers and crew, which would explain why no Mayday signal was given.