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

Operation Searchlight

Operation Searchlight was a planned military operation carried out by the Pakistan Army to curb the Bengali nationalist movement in the erstwhile East Pakistan in March 1971. Ordered by the central government in West Pakistan, this was seen as the sequel to "Operation Blitz" which had been...

 in March 1971. Indian Army Eastern Command was tasked with defending the northern and eastern borders and fighting the insurgencies in Nagaland

Nagaland

Nagaland is a state in the far north-eastern part of India. It borders the state of Assam to the west, Arunachal Pradesh and part of Assam to the north, Burma to the east and Manipur to the south. The state capital is Kohima, and the largest city is Dimapur...

, Mizoram

Mizoram

Mizoram is one of the Seven Sister States in North Eastern India, sharing borders with the states of Tripura, Assam, Manipur and with the neighbouring countries of Bangladesh and Burma. Mizoram became the 23rd state of India on 20 February 1987. Its capital is Aizawl. Mizoram is located in the...

 and Naxalites in West Bengal

West Bengal

West Bengal is a state in the eastern region of India and is the nation's fourth-most populous. It is also the seventh-most populous sub-national entity in the world, with over 91 million inhabitants. A major agricultural producer, West Bengal is the sixth-largest contributor to India's GDP...

 at that time. Mukti Bahini

Mukti Bahini

Mukti Bahini , also termed as the "Freedom Fighters" or FFs, collectively refers to the armed organizations who fought against the Pakistan Army during the Bangladesh Liberation War. It was dynamically formed by Bengali regulars and civilians after the proclamation of Bangladesh's independence on...

, aided by the Indian army through Operation Jackpot

Operation Jackpot

For the 1983–1986 South Carolina drug investigation see Operation Jackpot Operation Jackpot was the codename assigned to several different operations during the Bangladesh Liberation War in 1971. The original "Operation Jackpot" was the logistical and training operation set up under the Indian Army...

, led the struggle against the Pakistan army while the Indian army readied for intervention. General MAG 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 intanfry 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 IVth and the XXXIIIrd for operations in Bangladesh, and created a new corps (II) besides reorganized the 101st Communication Zone as a combat formation. On 21st November, 1971, Indian and Bangladesh forces were put under a joint command structure, led by Lt. Gen. Jagjit Singh Aurora

Jagjit Singh Aurora

Lieutenant General Jagjit Singh Aurora was the General Officer Commanding-in-Chief of the Eastern Command of the Indian Army during the Indo-Pakistani War of 1971...

, and this force came to be known as Mitro Bahini

Mitro Bahini

Mitro Bahini was the alliance of the Indian Army and the then-East Pakistani Mukti Bahini that engaged the Pakistani forces in December 1971 during the Bangladesh Liberation War. The alliance provided the final blow to the already weakened Pakistan Army which surrendered thirteen days after the...

. In addition to 29 BSF battalions, Mukti Bahini guerrillas operating near the border or awaiting deployment in camps inside India were organized into infantry companies and attached to various Indian formations. Mitro Bahini Order of Battle on December 3, 1971 was:

Indian Army Eastern Command HQ: Fort William

Fort William, India

Fort William is a fort built in Calcutta on the Eastern banks of the River Hooghly, the major distributary of the River Ganges, during the early years of the Bengal Presidency of British India. It was named after King William III of England...

, Kolkata

Kolkata

Kolkata , formerly known as Calcutta, is the capital of the Indian state of West Bengal. Located on the east bank of the Hooghly River, it was the commercial capital of East India...

GOC (Indian Army): Lt. General Jagjit Singh Aurora

COS: Maj. Gen. JFR Jacob

Director Military Operations: Major General Inder Gill

Director Operation Jackpot

Operation Jackpot

For the 1983–1986 South Carolina drug investigation see Operation Jackpot Operation Jackpot was the codename assigned to several different operations during the Bangladesh Liberation War in 1971. The original "Operation Jackpot" was the logistical and training operation set up under the Indian Army...

: Lt. Gen. B.N. ‘Jimmy’ Sirkar

Bangladesh Forces Liaison: Group Captain A.K. Khandkar,
HQ: 8, Theater Road, Kolkata

Units attached to Eastern Command but outside Bangladesh operational area:

From IV corps:

• 2nd Mountain division in North eastern border
• 5th Mountain division in North eastern border

From XXXIII corps:

• 17th Mountain division in Sikkim
  Sikkim
  Sikkim is a landlocked Indian state nestled in the Himalayan mountains...
  
  
• 27th Mountain division in Sikkim

Eastern Command Reserve:

• 6th Mountain division less brigade HQ: Cooch Bihar CO: Maj. Gen P.C. Reddy
  • 2 Engineer Regiments and bomb disposal group

Corps: Bengal Area

CO: Maj. Gen. J.P. Chowdhury HQ: Kolkata

• • 1/3 Gurkha Battalion
  • 11 Bihar
  • 12 Garh Rifel
  • Engineers and bomb disposal units

Sector: Western Sector

Area of Operation: Khulna

Khulna

Khulna is the third largest city in Bangladesh. It is located on the banks of the Rupsha and Bhairab rivers in Khulna District. It is the divisional headquarters of Khulna Division and a major industrial and commercial center. It has a seaport named Mongla on its outskirts, 38 km from Khulna...

, Jessore, Kushtia and Faridpur

Faridpur District

Faridpur is a district in central Bangladesh. It is a part of the Dhaka Division. Faridpur District has a population of over 1.7 million people and is situated on the banks of the Padma river . It is bordered by Madaripur, Narail, Rajbari, Magura, Shariatpur, Gopalgonj, Dhaka and Manikganj...

 districts

Corps: II

CO: Lt. Gen T.N. ‘Tappy’ Raina, HQ: Krishnanagar, West Bengal

West Bengal

West Bengal is a state in the eastern region of India and is the nation's fourth-most populous. It is also the seventh-most populous sub-national entity in the world, with over 91 million inhabitants. A major agricultural producer, West Bengal is the sixth-largest contributor to India's GDP...

• • 8th Mountain Artillery Brigade
  • 58th, 68th and 263rd Engineering Regiments

9th Infantry Division

CO Maj. Gen. Dalbir Singh

• 32 Infantry Brigade – Brig. M Tewari
• 42 Infantry Brigade – Brig. J. M. Jhoria
• 350 Infantry Brigade – Brig. H. S. Sandhu
• 9th Artillery Brigade
  • 45th Cavalry Regiment (PT-76
    PT-76
    The PT-76 is a Soviet amphibious light tank which was introduced in the early 1950s and soon became the standard reconnaissance tank of the Soviet Army and the other Warsaw Pact armed forces. It was widely exported to other friendly states, like India, Iraq, North Korea and North Vietnam. Overall,...
    
    s)
  • 102nd Engineer Regiment
• Mukti Bahini Sector #9 – Captain Jalil

4th Mountain Division

CO: Maj. Gen. M.S. Barar HQ: Krishnanagar

• 7th Mountain Brigade – Brig. Zail Singh
• 41st Mountain Brigade – Brig. Tony Michigan
• 62nd Mountain Brigade - Brig. Rajinder Nath
• 4th Mountain Artillery Brigade
• Mukti Bahini Sector #8 – Lt. Col. M.A. Manzoor

North Western Sector

Area of Operation: Rajshahi

Rajshahi

The city of Rajshahi is the divisional headquarters of Rajshahi division as well as the administrative district that bears its name and is one of the six metropolitan cities of Bangladesh. Often referred to as Silk City and Education City, Rajshahi is located in the north-west of the country and...

, Bogra

Bogra

Bogra is a town, and one of the oldest towns in northern Bangladesh. It is a centre of commerce and trade within the Bogra District and located under the Rajshahi Division. Bogra is sometimes described as the nerve centre of Northern Bangladesh. Amongst many notable activities, it has been hosting...

, Dinajpur and Rangpur

Rangpur District

The district of Rangpur have 4924 mosques, 480 temples, 43 churches and six tombs.In an anthropologic view most people of Rangpur are having Rajbagshi blood in their veins...

 districts

Corps: XXXIII

CO: Lt. Gen. M. L. Thapan HQ: Siliguri

Siliguri

Siliguri is a city in the Indian state of West Bengal. It is located in the Siliguri Corridor or Chicken's Neck - a very narrow strip of land linking mainland India to its north-eastern states. It is also the transit point for air, road and rail traffic to the neighbouring countries of Nepal,...

, West Bengal

• Corps Artillery Brigade
• 471st Engineering Brigade – Colonel Suri
• 50th Independent Parachute Brigade – Brig M. Thomas
  • 235th Army Engineering Regiment
• MF Brigade – Brig. Prem Singh
• Mukti Bahini Sector #7 – Lt. Col. Q.N. Zaman
• 71st Mountain Brigade – Brig. P. N. Kathpalia
• Mukti Bahini Sector #6 – Wing Commander Mohammad K. Bashar

20th Mountain Division

CO: Maj. Gen. Lachman Singh HQ: Balurghat

Balurghat

Balurghat is the headquarters of the Dakshin Dinajpur district of West Bengal in India. Hili Balurghat is the headquarters of the Dakshin Dinajpur district of West Bengal in India. Hili Balurghat is the headquarters of the Dakshin Dinajpur district of West Bengal in India. Hili (Bangladesh...

, West Bengal

• 66th Mountain Brigade – Brig. G. S. Sharma
• 165th Mountain Brigade – Brig. R. S. Pannu
• 202nd Mountain Brigade – Brig. F. P. Bhatty
• 3rd Armoured Brigade (63rd Cavalry (T-55
  T-55
  The T-54 and T-55 tanks were a series of main battle tanks designed in the Soviet Union. The first T-54 prototype appeared in March 1945, just before the end of the Second World War. The T-54 entered full production in 1947 and became the main tank for armored units of the Soviet Army, armies of...
  
  s) and 69th Armored Regiment (PT-76
  PT-76
  The PT-76 is a Soviet amphibious light tank which was introduced in the early 1950s and soon became the standard reconnaissance tank of the Soviet Army and the other Warsaw Pact armed forces. It was widely exported to other friendly states, like India, Iraq, North Korea and North Vietnam. Overall,...
  
  s) – Brig G. Singh Sidhu
• 20th Mountain Artillery Brigade
  • 13th Engineering Regiment

• 340th Mountain Brigade Group – Brig. Joginder Singh
  • 97th Mountain Regiment

6th Mountain Division

(Eastern Command HQ Reserve)
CO Maj. Gen. P. C. Reddy HQ: Kooch Bihar, West Bengal

• 9th Mountain Brigade – Brig. Tirit Varma
• 99th Mountain Brigade -
• 6th Mountain Artillery Brigade
  • 51st Engineer Regiment

101st Communication Zone

CO: Maj. Gen. Gurbax Singh Gil HQ: Guwahati, Assam

Assam

Assam , also, rarely, Assam Valley and formerly the Assam Province , is a northeastern state of India and is one of the most culturally and geographically distinct regions of the country...

• 312 Air Defence Brigade
• 342 Ind. Air Defence Brigade
  • 56th Mountain Regiment plus Engineers

• 95th Mountain Brigade – Brig. Hardev Singh Kler
• FJ Sector Brigade – Brig. Sant Singh
• Mukti Bahini Sector #11 – Lt. Col. Abu Taher
• 167th Infantry Brigade – Brig. Irani (allotted after December 8, 1971)
• 5th Mountain Brigade (allotted after December 8th, 1971)

Eastern Sector

Area of Operation: Sylhet

Sylhet

Sylhet , is a major city in north-eastern Bangladesh. It is the main city of Sylhet Division and Sylhet District, and was granted metropolitan city status in March 2009. Sylhet is located on the banks of the Surma Valley and is surrounded by the Jaintia, Khasi and Tripura hills...

, Comilla

Comilla

Comilla is a city in south-eastern Bangladesh, located along the Dhaka-Chittagong Highway. It is the administrative center of the Comilla District, part of the Chittagong Division. The Eastern Wing of Bangladesh Highway Police is located in Comilla....

, Noakhali & Chittagong

Chittagong

Chittagong ) is a city in southeastern Bangladesh and the capital of an eponymous district and division. Built on the banks of the Karnaphuli River, the city is home to Bangladesh's busiest seaport and has a population of over 4.5 million, making it the second largest city in the country.A trading...

 districts

IV Corps

CO Lt. General Sagat Singh HQ: Agartala, Tripura

Tripura

Tripura is a state in North-East India, with an area of . It is the third smallest state of India, according to area. Tripura is surrounded by Bangladesh on the north, south, and west. The Indian states of Assam and Mizoram lie to the east. The capital is Agartala and the main languages spoken are...

• Corps Artillery Brigade
• Three Independent Tank Squadrons
  • 4th, 62nd, 234th Engineer Regiments and support elements

8th Mountain Division

CO: Maj. Gen. K.V. Krishna Rao

• Echo Force Brigade – Brig. Wadeker
• Mukti Bahini Sector #5 – Major Mir Shawkat Ali
• 59th Mountain Brigade – Brig C. A. Quinn
• 81st Mountain Brigade – Brg. R. C. V. Apte
• 2nd Mountain Artillery Brigade
• Mukti Bahini Sector #4 – Lt. Col. C.R. Dutta

57th Mountain Division

CO: Maj. Gen. B.F. Gonsalves

• Mukti Bahini S Force Brigade – Lt. Col K.M. Shafiullah
• 311th Mountain Brigade – Brig. Mishra
• 73rd Mountain Brigade – Brig. Tuli
• 61st Mountain Brigade – Brig. Tom Pande
• 57th Mountain Artillery Brigade
• Mukti Bahini Sector #3 – Maj. A. N. Nuruzzaman
• Mukti Bahini Sector #2 – Maj. A.T.M Haider
  • 15th Engineering Regiment

23rd Mountain Division

CO: Maj. Gen. R.D. Hira

• 301st Mountain Brigade – Brig. H. S. Sodhi
• 181st Mountain Brigade – Brig. Y. C. Bakshi
• 83rd Mountain Brigade – Brig. B. S. Sandhu
• 23rd Mountain Artillery Brigade
• Kilo Force Brigade – Brig. Ananda Swaroop containing:
  • Mukti Bahini Sector #1 – Major Rafiqul Islam
  • Mukti Bahini K Force Brigade – Major Salek Chowdhury
  • Mizo Range Hills Brigade

Indian Navy

Indian Navy

The Indian Navy is the naval branch of the armed forces of India. The President of India serves as the Commander-in-Chief of the Navy. The Chief of Naval Staff , usually a four-star officer in the rank of Admiral, commands the Navy...

 Eastern Fleet

CO: Vice Admiral N. Krishnnan HQ: Vishakhapatnam, Andhra Pradesh

Andhra Pradesh

Andhra Pradesh , is one of the 28 states of India, situated on the southeastern coast of India. It is India's fourth largest state by area and fifth largest by population. Its capital and largest city by population is Hyderabad.The total GDP of Andhra Pradesh is $100 billion and is ranked third...

Fleet Commander: Rear Admiral S. A. Sharma

A liaison officer from the Navy was posted at Fort William to coordinate matters with the Army Eastern Command. The fleet was at its peacetime standing when radio intercepts warned of PNS Ghazi entering the Bay of Bengal. INS Vikrant and part of the fleet was moved to the Andamans as a result.

• INS Vikrant
  INS Vikrant
  INS Vikrant was a Majestic-class light aircraft carrier of the Indian Navy.Her keel was laid down on 12 November 1943 by Vickers-Armstrong on the Tyne and she was launched on 22 September 1945....
  
  – Captain Sawraj Prakash (Majestic class light Aircraft Carrier)
• INS Brahmaputra – Captain J.C. Puri (Leopard class frigate
  Leopard class frigate
  The Type 41 or Leopard class were a class of anti-aircraft defence frigates built for the Royal Navy and Indian Navy in the 1950s. These ships were designed to provide anti-aircraft escorts to convoys, as a result they were not built for fleet speeds and made only...
  
  )
• INS Beas – Captain L. Ram Das (Leopard Class Frigate)
• INS Kamrota – Captain A.P. Awati (Petya class frigate
  Petya class frigate
  The Petya Class was the NATO reporting name for a class of light frigates built for the Soviet Navy in the 1960s. The Soviet Designation was Storozhevoi Korabl Project 159.-Design:...
  
  )
• INS Kavaratti - Captain S. Paul (Petya class frigate)
• INS Rajput – Lt. Commander Inder Singh (destroyer)
• INS Kalvari – (Submarine)
• INS Khandari – Commander R. J. Milan (Submarine)
  • INS Panvel – Lt. Com. G.R. Naroha (Gunboat)
  • INS Pulikat – Lt. Com. S. Krishnnan ( Gunboat)
  • INS Panaji – Lt. Com. R. Gupta (Gunboat)
  • INS Akshay – Lt. Com. S.D. Moore (Gunboat)
    • INS Gharial – Lt. Commander U. Dabir (Landing Ship)
    • INS Gildar – Lt. Commander A.K. Sharma (Landing Ship)
    • INS Maggar – Lt. Commander AT. N. Singhal (Landing Ship)

Bangladesh Navy

Bangladesh Navy

The Bangladesh Navy is the naval arm of the Bangladesh Armed Forces. At present the navy is mostly limited to coastal patrolling, however it is implementing an ambitious procurement and expansion program to ensure the security of Bangladesh's maritime boundary...

2 gunboats under Indian officers and crewed by Bengali seamen were engaged in Operation Hotpants prior to December 3, 1971, harassing merchant traffic to East Pakistan and laying mines on the waterways. After December 6th, when the Indian Government recognized Bangladesh as a sovereign nation, the crew wore uniforms of their respective organizations.

Squadron CO: Commander N.M Samant (On deputation from Indian Navy)

• • BNS Palash – Lt. A.K. Mitra (On deputation fom Indian Navy) (Gunboat)
  • BNS Padma – Lt. Commander J.K. Rai Chowdhury (Indian Navy) (Gunboat)

Indian Air Force

Indian Air Force

The Indian Air Force is the air arm of the Indian armed forces. Its primary responsibility is to secure Indian airspace and to conduct aerial warfare during a conflict...

 Eastern Command

CO: Air Marshal H. C. Dewan, Temporary advanced HQ at Fort William

Prior to 1971, Indian Air Force had two command centers dealing with the East, Eastern Command (HQ Shillong

Shillong

-Connectivity:Although well connected by road, Shillong has no rail connection and a proper air connection. Umroi Airport exists but has only limited flights.-Roadways:Shillong is well connected by roads with all major north eastern states...

) responsible for the North Eastern Border, and the Central (HQ Allahbad), looking after areas south of the Ganges river

Ganges River

The Ganges or Ganga, , is a trans-boundary river of India and Bangladesh. The river rises in the western Himalayas in the Indian state of Uttarakhand, and flows south and east through the Gangetic Plain of North India into Bangladesh, where it empties into the Bay of Bengal. By discharge it...

. Air Chief Marshal P.C Lal formed an advance HQ at Fort William after consultation with Maj. Gen Jacob to coordinate operations with the army before the start of the war.

Western Sector:

• No. 7 Squadron (Battle Axes): Hawker Hunter
  Hawker Hunter
  The Hawker Hunter is a subsonic British jet aircraft developed in the 1950s. The single-seat Hunter entered service as a manoeuvrable fighter aircraft, and later operated in fighter-bomber and reconnaissance roles in numerous conflicts. Two-seat variants remained in use for training and secondary...
  
   F. MK 56 and 2 F. MK 1 - Bagdogra
  Bagdogra
  Bagdogra is a small town in the Darjeeling district of West Bengal, India, which is surrounded by tea gardens. Bagdogra is well connected by rail and air to the rest of the country. Bagdogra Airport is the only airport in North Bengal, which is now an International Airport. -References:...
  
   (WC Ceolho, then WC Suri). The squadron was moved Chamb after December 12.
• No. 14 Squadron (Bulls): Hawker Hunter F. MK 56 - Kalaikudda (WC Sundersan) - Fighter
• No. 16 Squadron (Rattlers): Canberra
  English Electric Canberra
  The English Electric Canberra is a first-generation jet-powered light bomber manufactured in large numbers through the 1950s. The Canberra could fly at a higher altitude than any other bomber through the 1950s and set a world altitude record of 70,310 ft in 1957...
  
   - Kalaikudda - (WC Gautum) - Bomber
• No. 22 Squadron (Swifts): Folland Gnat
  Folland Gnat
  The Folland Gnat was a small, swept-wing British subsonic jet trainer and light fighter aircraft developed by Folland Aircraft for the Royal Air Force, and flown extensively by the Indian Air Force....
  
   MK 1 Dum Dum
  Dum Dum
  Dum Dum is a city and a municipality in North 24 Parganas district in the state of West Bengal, India. It is a neighbourhood in North-west Kolkata and the location of Netaji Subhash Chandra Bose International Airport, formerly Dum Dum Airport.Dum Dum is a well known place in greater Kolkata...
  
  , then Kalaikudda, then Calcutta (WC Sikand)
• No. 30 Squadron (Charging Rhinos): Mig 21 FL - Kalaikudda (WC Chudda) - Interceptor
• No. 221 Squadron (Valiants): Su-7 BMK - Panagarh
  Panagarh
  Panagarh is a small town in India, located in Kanksa police station of Durgapur subdivision in Bardhaman District of West Bengal. Both the Indian Army and Air Force have their establishment here. An airport is also located here which is extensively used by Indian Air Force.-Geography:Panagarh is...
  
   (WC Sridharan) – Fighter/Bomber
• No. 104 (Alluitte 3) and No. 104 (Mi-4) Heli units

North East and North Western Sector:
CO: Air Vice Marshal Devasher HQ: Shillong

• No. 4 Squadron (Oorials): Mig 21 FL - Gauhati (Wing Commander JV Gole)
• No. 15 Squadron (Flying Lancers): Folland Gnat - Gauhati then Agortala (WC Singh)
• No. 17 Squadron (Golden Arrows): Hawker Hunter F MK 56 - Hashimara (WC Chatrath)
• No 37 Squadron (Black Panthers): Hawker Hunter F MK 10 - Hashimara (WC Kaul)
• No. 24 Squadron (Hunting Hawks): Folland Gnat Gauhati (WC Bhadwar)
• No. 28 Squadron (First Supersonics): Mig 21FL Gauhati (WC Bishnu)
• No. 105 (Mi-4) and 121 (Alouette III) Helicopter Squadrons - Agartola

Bangladesh Air Force

Bangladesh Air Force

The Bangladesh Air Force , is the air arm of the Bangladesh Armed Forces. Bangladesh Air Force currently employs more than 22,000 personnel including 600+ Pilots.-History:...

: Kilo Flight
CO: Flight Lt. Sultan Mahmud

Sultan Mahmud

Sultan Mahmud may refer to:*Mahmud I , Sultan of the Ottoman Empire*Mahmud II , Sultan of the Ottoman Empire*Mahmud of Ghazni , Sultan of Persia in the 11th century...

 HQ: Dimapur

Dimapur

Dimapur in Nagaland is bounded by Kohima district on the south and east, Karbi Anglong district of Assam on the West, the Karbi Anglong and stretch of Golaghat District of Assam, in the west and the north...

Nagaland, then Agartala

This unit was formed by Bengali pilots and technicians defecting from the Pakistan Air Force. Flying light aircraft donated by India, they launched attacks on depots and communication lines on December 2, 1971, before the start of the war. The unit relocated to Agartala and then Shamshernagar after December 3, 1971.