After the liberation, Ahmad was appointed the Minister of Power, Irrigation and Flood Control in 1972 as part of the Second Sheikh Mujib cabinet. In 1973, he took charge of the Ministry of Commerce in the Third Sheikh Mujib cabinet. He was a member of the executive committee of Bangladesh Krishak Sramik Awami League (BAKSAL) which was formed in 1975. Presidency Sheikh Mujib and all members of his family, except his daughters, who were in West Germany at the time, were assassinated by a group of army personnel on 15 August. Ahmad immediately took control of the government, proclaiming himself President. All three services chiefs were dismissed and replaced by next in line seniors. Major General Ziaur Rahman was appointed Chief of Army Staff of the Bangladesh Army, replacing K M Shafiullah. Air Vice Marshal A. K. Khandekar was replaced by AVM M G Ghulam Tawab. Mushhtaq reportedly praised the plotters who killed Sheikh Mujibur Rahman calling them Shurjo Shontan (sons of the sun). Mushtaq Ahmad also ordered the imprisonment of leaders Syed Nazrul Islam, Tajuddin Ahmad, A. H. M. Qamaruzzaman and Muhammad Mansur Ali. He replaced the national slogan of Joy Bangla with Bangladesh Zindabad slogan and changed the name Bangladesh Betar to 'Radio Bangladesh'. He proclaimed the Indemnity Ordinance, which granted immunity from prosecution to the assassins of Mujib. Mujib's daughters Sheikh Hasina Wazed and Sheikh Rehana were barred from returning to Bangladesh from abroad. BAKSAL and pro-Mujib political groups were dissolved. On 3 November, in what became infamously known as the "Jail Killing Day", the four imprisoned leaders Tajuddin Ahmad, Syed Nazrul Islam, A. H. M. Qamaruzzaman, and Muhammad Mansur Ali, who had refused to co-operate with Mostaq, were killed inside Dhaka Central Jail by a group of army officers on the instruction of President Khondaker Mostaq Ahmad. However, Mushtaq Ahmad was ousted from power on 6 November following a coup on 3 November led by Brigadier Khaled Mosharraf and Colonel Shafat Jamil among others. Later life and legacy Ahmad was imprisoned by Brigadier General Khaled Mosharraf and later by the Ziaur Rahman administration until 1978. Upon his release, he formed Democratic League and attempted to resuscitate his political career, but to no avail. He spent his last years in Dhaka and died on 5 March 1996. Ahmad was named in the investigation of the murder of Sheikh Mujib launched in 1996 by his daughter Sheikh Hasina,