1965: China accuses India of preventing livestock from grazing within its territory along Sikkim border. Warning is issued in September as Indo-Pak war simmers.
1965: China sends troopers on probe missions along Sikkim-Tibet border. Seven border intrusions are made between September and December. India responds firmly, but does not provoke a full conventional conflict.
1967: In September, Chinese army launches a direct attack on Indian troopers in Nathu La. For six days in September, there are skirmishes, including exchange of heavy artillery fire. Chinese troopers try to push into Indian territory. Attack is repulsed by India.
1967: The Chola incident breaks out between Indian and Chinese troopers in Sikkim from October 1 to 10. India loses 88 men and 163 are wounded. The Chinese lose 300 men and another 450 are wounded in Nathu La and another 40 at Chola.
1986: The Chinese begin building permanent military structures on Indian territory in Tawang district of Arunachal Pradesh, forcing India to deploy more troops. After a standoff lasting months, the Chinese withdraw, thanks to then Army chief General K Sundarji’s amazing military planning and deployment.