At 01:30 on 26 March 1971 (UTC+6), Sheikh Mujibur Rahman, the president of the All-Pakistan Awami League (AL) and the newly premier-elect in the 1970 Pakistani general election, was arrested by the Pakistan Army's Special Service Group from his private residence in Dacca, East Pakistan, Pakistan (present-day Bangladesh). The arrest operation was codenamed Operation Big Bird and occurred with Operation Searchlight. Following his arrest, Mujib was sent to Jail in Lyallpur, and in 2 August, it was announced that he would be tried in a military tribunal behind closed doors. The tribunal brought charges of treason against him.
Immediately after Mujib's arrest, following a month-long non-cooperation movement, the Bangladesh Liberation War began, and the Provisional Government of Bangladesh was formed, declaring Mujib as its president. In 4 December, the military tribunal sentenced him to death, although the verdict was kept secret. However, before the sentence could be carried out, Bangladesh and India's joint Allied Forces launched an offensive into East Pakistan, leading to the surrender of the Pakistan Army in Dacca on 16 December. After the surrender, the government of Yahya Khan collapsed, and following the rise of Zulfikar Ali Bhutto as the new Pakistani president, Mujib was released on 8 January 1972.