March to June 1971
Leaflets and pamphlets played an important role in driving public opinion during the war. At first resistance was spontaneous and disorganized, and was not expected to be prolonged.[43] But when the Pakistani Army cracked down upon the population, resistance grew. The Mukti Bahini became increasingly active. The Pakistani military sought to quell them, but increasing numbers of Bengali soldiers defected to the underground "Bangladesh army". These Bengali units slowly merged into the Mukti Bahini and bolstered their weaponry with supplies from India. Pakistan responded by airlifting in two infantry divisions and reorganizing their forces. They also raised paramilitary forces of Razakars, Al-Badrs and Al-Shams (who were mostly members of Jamaat-e-Islami and other Islamist groups), as well as other Bengalis who opposed independence, and Bihari Muslims who had settled during the time of partition. The Bangladesh government-in-exile was formed on 17 April at Mujib Nagar.
June – September 1971
Bangladesh Forces command reorganisation and reinforcement conference on known as the Sector Commanders Conference 1971 11 July - 17th July was presided over by Prime Minister Tajuddin and Gen. Osmani. This conference was significant for shaping and organizing the freedom struggle. The official creation of Bangladesh Forces, its command structuring, sector reorganization, reinforcement and appointing war commanders was its principal focus. Colonel Muhammad Ataul Gani Osmani received his promotion to General and reinstated from retirement as active duty into the armed forces of Bangladesh as its senior most official. Principal participants of this conference was Squadron Leader M. Hamidullah Khan, Major Ziaur Rahman, Wing Commander Bashar, Major Jalil, Captain Haider, Lt. Col. Abdur Rab and Group Captain A.K. Khandaker. Lt. Col. Rab was appointed as Chief of Bangladesh Army Staff and Group Captain Karim Khandaker as Osmanis deputy and later Chief of Air Staff Bangladesh Air Force. In this meeting, Bangladesh was divided into Eleven Sectors under Sector Commanders. Each sector was further structured into a combination of sub-sectors, each commanded by a Sub-Sector Commander.
The 10th Sector was directly placed under the Commander in Chief and included the Naval Commandos as the C-in-Cs special force. These commandos were later absorbed into the Bangladesh Navy. Sector Commanders directed the guerrilla warfare against West Pakistani forces. For better efficiency in military operations each of the sectors were divided into a number of sub-sectors.
Bangladesh was divided into Eleven Sectors each with a sector commander chosen from defected officers of Pakistan army who joined the Bangladesh Forces under General M A G Osmani to conduct guerrilla operations and train fighters. Most of their training camps were situated near the border area and were operated with measured assistance from India. The 10th Sector was directly placed under Commander in Chief (C-in-C) and included the Naval Commandos and C-in-Cs special force.[44] Three brigades (11 Battalions) were raised for conventional warfare; a large guerrilla force (estimated 100,000) was trained.
Guerrilla operations, which slackened during the training phase, picked up after August. Economic and military targets in Dhaka were attacked. The major success story was Operation Jackpot, in which naval commandos mined and blew up berthed ships in Chittagong on 16 August1971. Pakistani reprisals claimed lives of thousands of civilians. The Indian army took over supplying the Mukti Bahini from the BSF. They organised six sectors for supplying the Bangladesh forces.
October – December 1971
Bangladesh conventional forces attacked border outposts. Kamalpur, Belonia and Battle of Boyra are a few examples. 90 out of 370 BOPs fell to Bengali forces. Guerrilla attacks intensified, as did Pakistani and Razakar reprisals on civilian populations. Pakistani forces were reinforced by eight battalions from West Pakistan. The Bangladeshi independence fighters even managed to temporarily capture airstrips at Lalmonirhat and Shalutikar.[45] Both of these were used for flying in supplies and arms from India. Pakistan sent 5 battalions from West Pakistan as reinforcements.
See also: Bangladesh War timeline
Indian involvement
Illustration showing military units and troop movements during the war.
See also: Indo-Pakistani War of 1971
Wary of the growing involvement of India, the Pakistan Air Force (PAF) launched a pre-emptive strike on India. The attack was modelled on the Operation Focus employed by Israel Air Force during the Six-Day War. However, the plan failed to achieve the desired success and was seen as an open act of unprovoked aggression against the Indians.
Indian prime minister Indira Gandhi declared war on Pakistan and in aid of the Mukti Bahini, then ordered the immediate mobilisation of troops and launched the full-scale invasion. This marked the official start of the Indo-Pakistani War.
Three Indian corps were involved in the invasion of East Pakistan. They were supported by nearly three brigades of Mukti Bahini fighting alongside them, and many more fighting irregularly. This was far superior to the Pakistani army of three divisions[46]. The Indians quickly overran the country, bypassing heavily defended strongholds. Pakistani forces were unable to effectively counter the Indian attack, as they had been deployed in small units around the border to counter guerrilla attacks by the Mukti Bahini.[47] Unable to defend Dhaka, the Pakistanis surrendered on 16 December1971.
The speed of the Indian strategy can be gauged by the fact that one of the regiments of Indian army (7 Punjab now 8 Mechnised Inf Regiment) fought the liberation war along the Jessore and Khulna axis. They were newly converted to a mechanised regiment and it took them just 1 week to reach Khulna after capturing Jessore. Their losses were limited to just 2 newly acquired APCs (SKOT) from the Russians.
Indian Armys T-55 tanks on their way to Dhaka. Indias military intervention played a crucial role in turning the tide in favour of the Bangladeshi rebels. Indias external intelligence agency, the R&AW, played a crucial role in providing logistic support to the Mukti Bahini during the initial stages of the war. R&AWs operations, in then-East Pakistan, was the largest covert operation in the history of South Asia.
Pakistani response
Pakistan launched a number of armoured thrusts along Indias western front in attempts to force Indian troops away from East Pakistan. Pakistan tried to fight back and boost the sagging morale by incorporating the Special Services Group commandos in sabotage and rescue missions. This, however, could not stop the juggernaut of the advancing columns, whose speed and power were too much to contain for the Pakistani Army.
The air and naval war
The Indian Air Force carried out several sorties against Pakistan, and within a week, IAF aircraft dominated the skies of East Pakistan. It achieved near-totalair supremacy by the end of the first week as the entire Pakistani air contingent in the east, PAF No.14 Squadron, was grounded due to Indian airstrikes at Tejgaon, Kurmitolla, Lal Munir Hat and Shamsher Nagar. Sea Hawks from INS Vikrant also struck Chittagong, Barisal, Coxs Bazar, destroying the eastern wing of the Pakistan Navy and effectively blockading the East Pakistan ports, thereby cutting off any escape routes for the stranded Pakistani soldiers. The nascent Bangladesh Navy (comprising officers and sailors who defected from Pakistani Navy) aided the Indians in the marine warfare, carrying out attacks, most notably Operation Jackpot.