Confrontation At Thag La
In June 1962, Indian forces had established an outpost at Dhola, on the southern slopes of Thag La Ridge, overlooking the village of Le in Tibet. Based on the treaty map of the 1914 Simla Convention, the McMahon Line lay at 27°44’30’’N. However, Dhola post lay about one mile (1.6 km) north of the McMahon Line The Indian government maintained that the intention of the McMahon Line was to set the border along the highest ridges, and that the international border fell on the highest ridges of Thag La, about 3 to 4 miles (4.8 to 6.4 km) north of the line drawn by Henry McMahon on the treaty map. Brigadier John Dalvi would later write of this claim: "The Chinese had raised a dispute about the exact alignment of the McMahon Line in the Thag La Ridge area. Therefore the Thag La-Dhola area was not strictly territory that 'we should have been convinced was ours' as directed by the Prime Minister, Mr. Nehru, and someone is guilty of exceeding the limits prescribed by him."
In August, China issued diplomatic protests which accused India of violating even the McMahon Line, and Chinese soldiers began occupying positions at the top of Thag La, north of Indian positions.
On September 8, 1962, a 60-strong PLA unit descended from the heights and occupied positions which dominated one of the Indian posts at Dhola. Neither side opened fire for 12 days. Nehru had gone to London to attend a Commonwealth Prime Ministers' Conference and, when told of the act, said to the media that the Indian Army had instructions to "free our territory".
According to the official Indian history, a decision was made on September 9 to evict the Chinese from the southern part of the Thag La Ridge, by force, if necessary. Two days later, it was decided that "all forward posts and patrols were given permission to fire on any armed Chinese who entered Indian territory".
According to author Neville Maxwell, officers at the Indian Defense Ministry had expressed the concern that Indian maps showed Thag La as Chinese territory; they were told to ignore the maps. However, Nehru's directives to Defense Minister V.K. Krishna Menon were unclear, and the response, code named Operation LEGHORN, got underway only slowly. As the Chinese numbers were exaggerated to 600 instead of about 50 or 60, the 9 Punjab battalion, numbering 400 riflemen, was sent to Dhola.
By the time the Indian battalion reached the Thag La Ridge in the Chedong region on September 16, north of the McMahon Line, Chinese units controlled both banks of the Namka Chu River. The day after, India's Chief of the Army Staff Kaul ordered his men to re-take the Thag La Ridge. According to the official Indian history, on September 20, Indian eastern command ordered all Indian posts and patrols to engage any Chinese patrols within range of their weapons. On September 20, at one of the bridges on the river a firefight developed, killing nine Chinese and Indian soldiers. Skirmishes continued throughout September.
On 3 October, Zhou Enlai visited Nehru in New Delhi, promising there would be no war between the nations and reiterating his wishes to solve the dispute diplomatically.
On October 4, a special Border Command was created, under Lt. Gen. B.M. Kaul, tasked with evicting the Chinese from Dhola-Thag La October 10 was the planned date for Operation Leghorn. Because of the difficulties involved in directly assaulting and taking Thag La, Kaul made the decision instead to occupy nearby Yumtso La to the west, to position his troops behind and dominate the Chinese positions.
Brigadier John Dalvi, tasked with taking Yumtso La, argued that he lacked necessary supplies and resources to take the pass. On October 9, Kaul and Brigadier Dalvi agreed to send a patrol of 50 soldiers to Tseng Jong, the approach to Yumtso La, to occupy the position and provide cover before the rest of the battalion would move forward for the occupation of Yumtso La.
On October 10, these 50 Indian troops were met by an emplaced Chinese position of some 1,000 soldiers. The Chinese troops opened fire on the Indians believing that the Indians had intruded upon Chinese land. The Indians were surrounded by a Chinese positions which used mortar fire. However, they managed to hold off the first Chinese assault, inflicting heavy casualties. In the second assault, the Indians began their retreat, realising the situation was hopeless. The Indian patrol suffered 25 casualties, with the Chinese suffering 33. The Chinese troops held their fire as the Indians retreated, and then buried the Indian dead with military honors, as witnessed by the retreating soldiers. This was the first occurrence of heavy fighting in the war.
This attack had grave implications for India and Nehru tried to solve the issue, but by 18 October it was clear that the Chinese were preparing for an attack on India, with massive troop buildups on the border.
Read more about this topic: Events Leading To The Sino-Indian War