The Indo-Pak War of 1965 was the second major armed conflict between India and Pakistan, centered initially on Jammu & Kashmir and later expanding across the international border into Punjab and Rajasthan. The conflict followed a series of clashes in the Rann of Kutch and Pakistan's August 1965 Operation Gibraltar, which involved infiltration into Jammu & Kashmir. Pakistan subsequently launched Operation Grand Slam in the Chamb–Akhnoor sector on 1 September. India responded by expanding the conflict to the international border, including the Punjab sector. Major battles were fought at Chawinda, Phillora, Asal Uttar, Burki, Dograi and Haji Pir. The Indian Air Force and Pakistan Air Force also conducted extensive air operations. The fighting ended with a UN-backed ceasefire on 23 September 1965, followed by negotiations that resulted in the Tashkent Declaration in January 1966. The war did not resolve the underlying Kashmir dispute.