Mitro Bahini (Bengali language: মিত্রবাহিনী) ("Allied forces" in Bangla) was the alliance of the Indian Army and the Mukti Bahini ("Freedom Fighters" as representation of the Bangladeshi forces) that engaged the then Pakistani occupied forces on December, 6 in 1971 during the Bangladesh Liberation War. The alliance provided the final blow to the already weakened Pakistan Army which surrendered thirteen days after the formal declaration of war.