The Bengali population was angered when Prime Minister-elect Sheikh Mujibur Rahman was prevented from taking the office. Civil disobedience erupted across East Pakistan, with calls for independence. Mujib addressed a pro-independence rally of nearly 2 million people in Dacca (as Dhaka used to be spelled in English) on 7 March 1971, where he said, "This time the struggle is for our freedom. This time the struggle is for our independence." The flag of Bangladesh was raised for the first time on 23 March, Pakistan's Republic Day. Later, on 25 March late evening, the Pakistani military junta led by Yahya Khan launched a sustained military assault on East Pakistan under the code name of Operation Searchlight. The Pakistan Army arrested Sheikh Mujibur Rahman and flew him away to Karachi. However, before his arrest Mujib proclaimed the Independence of Bangladesh at midnight on 26 March which led the Bangladesh Liberation War to break out within hours. The Pakistan Army and its local supporters continued to massacre Bengalis, in particular students, intellectuals, political figures, and Hindus in the 1971 Bangladesh genocide. The Mukti Bahini, a guerrilla resistance force, also violated human rights during the conflict. During the war, an estimated 0.3 to 3 million people were killed and several million people took shelter in neighbouring India. Global public opinion turned against Pakistan as news of the atrocities spread; the Bangladesh movement was supported by prominent political and cultural figures in the West, including Ted Kennedy, George Harrison, Bob Dylan, Joan Baez, Victoria Ocampo and André Malraux. The Concert for Bangladesh was held at Madison Square Garden in New York City to raise funds for Bangladeshi refugees. The first major benefit concert in history, it was organised by Harrison and Indian Bengali sitarist Ravi Shankar.