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Bangladesh came into existence only in the year 1971. The Bangladesh Liberation War lasted for nine months. The Bangladesh Forces formed within 11 sectors led by General M.A.G. Osmani consisting of Bengali Regulars and Mukti Bahini conducted a massive guerilla war against the Pakistan Forces with all out support from the Indian Armed Forces. Jointly the Mitro Bahini achieved a decisive victory over Pakistan on December 16, 1971, with Indian Armed Forces taking over 90,000 prisoners of war. General Sam Manekshaw was the Chief of Army Staff at that time.