In 1962, the Indian Army was ordered to move to the Thag La ridge, located near the border between Bhutan and Arunachal Pradesh and about north of the disputed McMahon Line. Meanwhile, Chinese troops had also made incursions into Indian-held territory, and tensions between the two reached a new high when Indian forces discovered the road constructed by China in Aksai Chin. After a series of failed negotiations, the People's Liberation Army attacked Indian Army positions on the Thag La ridge. This move by China caught India by surprise; and on 12 October Nehru gave orders for the Chinese to be expelled from Aksai Chin. However, poor co-ordination among various divisions of the Indian Army, and the late decision to mobilise the Indian Air Force in vast numbers, gave China a crucial tactical and strategic advantage over India. On 20 October, Chinese soldiers attacked India from both the northwest and northeast, and captured large portions of Aksai Chin and Arunachal Pradesh.