Original sentence: By 1987, Beijing's reaction was similar to that in 1962 and this prompted many Western diplomats to predict war.Chinese troops could not move any further into the Valley and were forced to move sideways along the Thag La ridge, away from the valley.However, Indian foreign minister N.In 1980, Indian Prime Minister Indira Gandhi approved a plan to upgrade the deployment of forces around the Line of Actual Control to avoid unilateral redefinitions of the line.In 1984, squads of Indian soldiers began actively patrolling the Sumdorong Chu Valley in Arunachal Pradesh (formerly NEFA), which is north of the McMahon Line as drawn on the Simla Treaty map but south of the ridge which Indian claims is meant to delineate the McMahon Line.. The Indian team left the area before the winter.In the winter of 1986, the Chinese deployed their troops to the Sumdorong Chu before the Indian team could arrive in the summer and built a Helipad at Wandung.India also increased funds for infrastructural development in these areas.Sundarji, airlifted a brigade to the region.Surprised by the Chinese occupation, India's then Chief of Army Staff, General K.Tiwari and Prime Minister Rajiv Gandhi travelled to Beijing over the following months to negotiate a mutual de-escalation