Indian military sources revealed to national news outlets there on Tuesday that its troops had prevented the Chinese People’s Liberation Army (PLA) from illegally occupying an Indian mountain peak near the two countries’ border.

The sources – surfacing in multiple Indian media outlets such as the Times of India, WIO News, and Zee News – described the move as “preemptive” and resulting in the removal of hundreds of Chinese troops from disputed territory. The PLA soldiers were, the Indians believe, attempting to establish an illegal base on a mountain peak near Pangong Tso, a lake that straddles India’s Ladakh region and occupied Tibet. Indian troops have now established themselves there, instead, a move the Chinese Foreign Ministry condemned as an invasion.

Both India and China claim the location in question is part of their sovereign territory.

The exchange, which allegedly occurred this weekend and did not result in any significant casualties, is the most severe encounter between China and India on their border since the deadly military clash in the Galwan Valley, Ladakh, in June that left 20 Indian soldiers and an unknown number of Chinese soldiers dead. China refuses to acknowledge any casualties, though Indian officials claim they suffered at least as many deaths.

The Galwan Valley incident was the deadliest between the two countries in 45 years.

“Height occupied by Indian Army troops including a special operations battalion is south of Southern bank of Pangong Tso near Thakung. Height was lying dormant and can give strategic advantage to the side which holds it for controlling the southern bank of lake and areas around it,” unnamed “sources,” presumably on the Indian side, told the Times of India. The newspaper noted the incident reportedly occurred in difficult terrain at 15,000 feet above sea level.

The statement echoed what a spokesperson for the Indian Army, Col. Aman Anand, told reporters in a statement on Monday.

“On the night of August 29/30, PLA troops violated the previous consensus arrived at during military and diplomatic engagements over the ongoing standoff in Eastern Ladakh and carried out provocative military movements to change the status quo,” the Times of India quoted Anand as saying, adding that the troops “thwarted Chinese intentions to unilaterally change facts on the ground.”

Zee News, another Indian outlet, described the disputed mountain peak in question as a “black top” looking down on Pangong Tso that, had the PLA managed to establish an illegal camp there, would have granted it great latitude to spy on Indian border troop movements. To that end, the removal of PLA troops also included the removal of cameras and surveillance equipment that they had brought with them in addition to camping gear.

In a later report, the Times of India added the detail that China, according to Indian “sources” had moved 200 PLA troops close to the area, apparently attempted to establish a camp within India, and Indian troops confronted and physically removed them from the premises. The newspaper claimed that, while neither side publicly documented injuries, “scuffles” erupted between the two sides.

The Times added that India used its “Special Frontier Force” for the operation, which includes ethnic Tibetans who fled communism to India.

Outraged Chinese diplomats accused India of invading Chinese territory and needlessly escalating tensions.

“China never provoked any war or conflict and never occupied an inch of other country’s territory. China border troops never crossed the line. Perhaps there are some communication issues,” Chinese Foreign Ministry spokeswoman Hua Chunying said on Tuesday. “I think both sides should stick to facts and have goodwill in maintaining the bilateral relations and take concrete measures to safeguard peace, tranquillity along the border.”

China’s foreign minister, Wang Yi, similarly claimed that China only seeks “a policy of good-neighborliness” and accused India of cravenly violating it.

“With regard to the recent China-India border dispute, Wang said that China has always been committed to maintaining stability along the China-India border and will not be the first to complicate or escalate the situation,” the state-run Chinese propaganda outlet Global Times reported. “The boundary between China and India has not yet been demarcated, so there have been problems. China will firmly safeguard its sovereignty and territorial integrity, and ‘we are ready to manage all kinds of issues through dialogue with the Indian side.”

Ji Rong, a spokesman for the Chinese embassy in India, claimed New Delhi had “severely infringed” on Chinese sovereignty and “destroyed the regional peace and stability” of the border region.

The Global Times itself, in an editorial, demanded the PLA prepare for war.

“China needs to prepare to carry out a military struggle in the China-India border area. We should try our best to resolve frictions through peaceful means,” the editorial, published Tuesday, read. “But when India recklessly challenges China’s bottom line, China must not be soft. It must take military actions when necessary, and ensure it can win.”

The propaganda newspaper added a claim that, following multiple exchanges with India in which China has failed to securely hold Indian sovereign territory, read increasingly unlikely: “China is several times stronger than India, and India is no match for China.”

Chinese and Indian troops have coexisted on the border tensely for decades. Those tensions boiled up into military conflict in June, when Indian officials say their troops found a contingent of PLA soldiers erecting tents on sovereign Indian land in Ladakh. The Indian troops reportedly approached and confronted the Chinese soldiers, asking what they were doing there, and in response the PLA troops attacked them. As the rules of engagement for both sides prevent the use of firearms, the Chinese soldiers used sticks, rocks, and clubs wrapped in barbed wire to kill their Indian counterparts. Others reportedly died of hypothermia or fell off of cliffs. India reported at least 23 dead, including a high-ranking officer, and over 100 injuries.

China officially reported zero casualties. Indian officials said that at least twice the number of Chinese died as the number of Indians, a claim the Chinese Foreign Ministry denied without offering evidence or another number.

Indian Prime Minister Narendra Modi responded to the clash by visiting the Galwan Valley and personally meeting injured soldiers as they recovered. In a speech on the border, Modi told China, “the era of expansionism has come to an end” and warned that India’s soldiers are “better than everyone else in the world.”

Chinese dictator Xi Jinping has not addressed the Galwan Valley incident. Xi made a quick reference to “border security” in Tibet in remarks this weekend, the first of his words to come close to approaching the subject.

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