By late 1971, the intensification of the independence movement in erstwhile East Pakistan lead to the Bangladesh Liberation War between India and Pakistan . On 22 November 1971, 10 days before the start of a full-scale war, four PAF F-86 Sabre jets attacked Indian and Mukti Bahini positions at Garibpur, near the international border. Two of the four PAF Sabres were shot down and one damaged by the IAF's Folland Gnats. On 3 December, India formally declared war against Pakistan following massive preemptive strikes by the PAF against Indian Air Force installations in Srinagar, Ambala, Sirsa, Halwara and Jodhpur. However, the IAF did not suffer significantly because the leadership had anticipated such a move and precautions were taken. The Indian Air Force was quick to respond to Pakistani air strikes, following which the PAF carried out mostly defensive sorties.