Since the partition of British India in 1947 into the two separate and independent states of Pakistan and India, Pakistan has been closely aligned with the United States, relying primarily on American-supplied weapons to meet its military needs.
During a visit to Karachi, Pakistan, President Dwight Eisenhower promised to provide the government of Pakistan with modern jet bombers. In 1959, 24 B-57Bs and two B-57Cs from the inactivated 345th Tactical Bomber Group at Langley AFB in Virginia were ferried to Mauripur Air Base in Karachi, Pakistan to form the 7th and 8th Bomber Squadrons of the 31st Bomber Wing of the Pakistan Air Force.
At first, these planes were not equipped with an all-weather bombing system as had been originally promised. From 1963, all of the Pakistani B-57Bs were retrofitted with the RB-1A all-weather bombing system which gave them a somewhat longer nose shape than that of standard USAF B-57Bs. Some of the B-57s were also fitted with underwing points for the carriage of four extra fuel tanks, which gave them sufficient range to reach targets well inside India.
In addition, two RB-57F high-altitude reconnaissance aircraft were also supplied to Pakistan in the early 1960s.
In September of 1965, war broke out between Pakistan and India. The war began as a series of border clashes over the status of Kashmir, but the real orgin of the war dated back to the hatred and strife caused by the violent partition of British India in 1947 into separate Moslem and Hindu states. The first Pakistan Air Force bombing attack of the war was carried out by six B-57s based at Mauripur on September 6 when they struck at the Jamnagar airfield in the Rann of Kutch. Subsequent attacks were carried out on the Indian Air Force bases at Adampur and Pathankot. In addition, the B-57s struck successfully at the radar station at Amritsar which was directing Indian Air Force operations over West Pakistan.
The India-Pakistan war did not last long, because neither nation was capable of sustaining any sort of long conflict because military supplies had been cut off to both countries by the United States and Britain. On September 23, a cease-fire was arranged through the United Nations Security Council which arranged for a a mutual withdrawal of forces. By the time the the war ended on September 22, Pakistani B-57s had flown 167 sorties, dropping over 600 tons of bombs. Three B-57s were lost in action, along with one RB-57F electronics intelligence aircraft. With the cutoff of US aid to the Pakistan Air Force, a chronic shortage of spare parts resulted. This required that replacement parts not already in stock be made locally or old ones repaired.
General Agha Mohammad Yahya Khan seized power in Pakistan on March 25, 1969, proclaiming martial law and the introduction of military control of the government. He was shortly to be challenged by the crisis of eastern Pakistan. The Pakistan created in August of 1947 was composed ot two parts, or wings, known as East Pakistan and West Pakistan, separated from each other by a thousand miles of Indian territory. It proved difficult to create a single, unified nation out of the two wings, since the people of the two wings had quite different languages, cultures, and traditions, and suspicion and distrust grew between the two wings out of a perceived unfairness in representation within the government and the military. In addition, the East wing was relatively economically undeveloped in comparison to the West, which created further frictions. In March of 1971, large-scale unrest broke out in eastern Pakistan, which was systematically and brutally repressed by the Pakistani army during the next few months, leading to a full-scale civil war. Ziaur Rahman proclaimed the independence of the East wing as Bangladesh, and a Bangladeshi government of exile was formed in Calcuta. Tens of thousands of Bengalis were killed, and millions of refugees flowed into eastern India. The Pakistani crackdown was particularly alarming in its ferocity, leading to a world-wide protest by human-rights groups.
In response to the civil war and the influx of millions of refugees, India massed troops along the India-East Pakistani border. In response to these Indian moves, the Pakistani Air Force began to attack Indian targets in northern India on December 3. In response, the Indian army began a land, sea, and air invasion of East Pakistan. India and Pakistan were at war once again.
At the beginning of the war Nos 7 and 8 Squadrons had 15 B-57Bs and Cs. Although the reports are conflicting, it appears that at least four B-57s were lost in action in the 1971 war and perhaps even a fifth, reducing the effective PAF bomber strength to only ten or eleven aircraft. This brought about the disbandment of No 8 Squadron, with the remaining B-57s being concentrated in No 7 Squadron.
Indian forces quickly occupied all of East Pakistan, and all Pakistani forces in the east surrendered on December 16. Indian prime minister Indira Gandhi proclaimed a unilateral cease-fire on December 17. The military was thoroughly discredited by this defeat, and Yahya Khan was forced to resign on December 20. He was replaced by Zulfiqar Ali Bhutto, who gradually began a return to civilian rule.
The surviving PAF B-57Bs continued to serve until 1985, when they were finally replaced by the first batch of US-supplied F-16A Fighting Falcons.