On 6 September, both countries openly went to war following a series of minor skirmishes that preceded the 6th, when Pakistan was attacked by India from the Lahore-Burki sector during the dead of night (at 5 am). The war began following 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.