Mitro Bahini order of battle

The Indian Army had no standby force ready in 1971 with the specific task of attacking East Pakistan, one of the many reasons why India did not immediately intervene after Pakistan launched Operation Searchlight in March 1971. Indian Army's Eastern Command was tasked with defending the northern and eastern borders and fighting the insurgencies in Nagaland, Mizoram and Naxalites in West Bengal at that time.^[1]

Mukti Bahini, aided by the Indian army through Operation Jackpot, led the struggle against the Pakistan Army while the Indian Army readied for intervention. General M. A. G. Osmani, Commander-in-Chief Bangladesh Forces, had divided Mukti Bahini forces into 11 geographical sectors for command and control purpose. Mukti Bahini forces numbered 30,000 regular soldiers (including 3 brigades containing 8 infantry battalions and 3 artillery batteries) and at least 100,000 guerrillas by December 1971.

The Indian Army Eastern Command assembled two existing infantry corps, the IV Corps and the XXXIII Corps, for operations in Bangladesh, and created a new corps (II Corps)^[2] besides reorganising the 101 Communication Zone as a combat formation.^[3] On 21 November 1971, the Indian and Bangladesh forces were put under a joint command structure India Bangladesh force in the eastern theatre, led by Lieutenant General Jagjit Singh Aurora, and this force came to be known as Mitro Bahini. In addition to 29 battalions of the Border Security Force (BSF),^[4] Mukti Bahini guerrillas operating near the border or awaiting deployment in camps inside India were organised into infantry companies and attached to various Indian formations.