Tensions along the India-China border took an alarming shift on Tuesday after Chinese and Indian officials accused each other’s soldiers of firing warning shots, apparently after a long time in decades that light weapons had been used in the region.

Military activities along the unofficial border, which zigs and zags through high mountain ranges on Earth, are difficult to verify.
But consistent with a press release from the Chinese military, Indian troops on Monday “took the outrageous step of firing warning shots” near a Chinese patrol. India’s actions, the Chinese said, were “a grave military provocation of a vile character.”
Indian officials, however, denied their soldiers had fired any shots and said it had been the Chinese who broke the long tradition of refraining from using firearms, a protocol followed for many years.
Chinese soldiers “fired a couple of rounds within the air in an effort to intimidate” Indian troops, the Indian military said during a statement. “Despite the grave provocation,” the statement said, Indian troops “exercised great restraint and behaved in a mature and responsible manner.”
One thing is clear: The dispute that has been building on the Himalayan border that separates nuclear-armed powers is merely sharpening as their broader relationship steadily deteriorates.
In June, an enormous brawl broke out high within the mountains and Chinese troops beat to death 20 Indian soldiers.
In August, a soldier belonging to a secretive force of Tibetan refugees who work with the Indian army died after he stepped on a ground-emplaced mine whereas the Chinese avoided mentioning of casualties.

The two giants have engaged tens of thousands of reinforcements, backed by artillery, tanks, and fighter jets. In India, the clashes have sparked a wave of nationalism and further turned the general public against China, with street protests and boycotts of Chinese-made goods.

The 2,000-mile-long unmarked border between the countries has been a sore spot for many years. In 1962, both countries fought a war over it. China won, wrenching away an enormous but sparsely populated plateau from India.