Despite historical, cultural and ethnic links between them, relations between India and Pakistan have been "plagued" by years of mistrust and suspicion ever since the partition of India in 1947. The principal source of contention between India and its western neighbour has been the Kashmir conflict. After an invasion by Pashtun tribesmen and Pakistani paramilitary forces, the Hindu Maharaja of the Dogra Kingdom of Jammu and Kashmir, Hari Singh, and its Muslim Prime Minister, Sheikh Abdullah, signed an Instrument of Accession with New Delhi. The First Kashmir War started after the Indian Army entered Srinagar, the capital of the state, to secure the area from the invading forces. The war ended in December 1948 with the Line of Control dividing the erstwhile princely state into territories administered by Pakistan (northern and western areas) and India (southern, central and northeastern areas). Pakistan contested the legality of the Instrument of Accession since the Dogra Kingdom has signed a standstill agreement with it. The Indo-Pakistani War of 1965 started following the failure of Pakistan's Operation Gibraltar, which was designed to infiltrate forces into Jammu and Kashmir to precipitate an insurgency against rule by India. The five-week war caused thousands of casualties on both sides. It ended in a United Nations (UN) mandated ceasefire and the subsequent issuance of the Tashkent Declaration. India and Pakistan went to war again in 1971, this time the conflict being over East Pakistan. The large-scale atrocities committed there by the Pakistan army led to millions of Bengali refugees pouring over into India. India, along with the Mukti Bahini, defeated Pakistan and the Pakistani forces surrendered on the eastern front. The war resulted in the creation of Bangladesh.