Defence minister Rajnath Singh on Tuesday told Parliament that Chinese soldiers had tried to “transgress” the Line of Actual Control and “unilaterally change the status quo” in Yangtze in the Tawang sector of Arunachal Pradesh on Friday but were foiled by the Indian army.

He said there was a “physical scuffle leading to injuries to a few personnel on both sides”.

Rajnath’s statement stood out against that made by Prime Minister Narendra Modi at an all-party meeting after the Galwan killings. “Neither has anyone intruded into our frontier there, nor is any intruder there, nor is any of our posts occupied by someone else,” Modi had told Parliament on June 19, 2020, four days after 20 Indian soldiers were killed.

A defence ministry official, speaking anonymously, said on Tuesday: “Out of the 15-20 of our soldiers injured, 6 to 7 have suffered fractures in their hands and legs and are being treated at a Guwahati hospital.”

Sources in the security establishment and some military veterans described the Chinese action as “extremely serious” and “alarming”, arguing it mirrored the intrusions in eastern Ladakh where China is estimated to have occupied about 1,000sqkm of India-claimed territory since May 2020.

“The Chinese attempt was contested by our troops in a firm and resolute manner. The ensuing faceoff led to a physical scuffle in which the Indian army bravely prevented the PLA from transgressing into our territory and compelled them to return to their posts,” Rajnath told Parliament.

“I wish to share with this House that there are no fatalities or serious casualties on our side. Due to timely intervention of Indian military commanders, PLA (Chinese) soldiers went back to their locations.”

Rajnath said the matter had been taken up with the Chinese side through diplomatic channels. He added that the local commander had held a flag meeting with his Chinese counterpart on Sunday to discuss the matter in accordance with established mechanisms.

“The Chinese side was asked to refrain from such actions and maintain peace and tranquillity along the border,” the defence minister said.

Sources said the clash took place in the dark, around 3.15am, after more than 500 Chinese troops crossed the LAC and began vandalising Indian military posts. The Indian troops were initially outnumbered but reinforcements arrived within half an hour.

“Our troops were completely taken aback by the sudden aggression from the PLA troops in the dark. They (Chinese) were armed with clubs fitted with nails,” an Intelligence Bureau official said. The two sides first hurled stones at each other before getting engaged in hand-to-hand combat for a few hours.

The clash is the first since the violent confrontation of June 2020 in the Galwan Valley in eastern Ladakh, where 20 Indian soldiers and at least four Chinese troopers were killed. There too the Chinese had targeted Indian military posts in the dark and reportedly used similar clubs.

“The latest land-grab bid by the Chinese and the attack on Indian soldiers in Arunachal Pradesh is an extremely serious military aggression. It was a provocative and preplanned act, and the clash was similar to the Galwan Valley violence,” a former lieutenant general said.

A retired colonel said that after altering the status quo at multiple friction points in Ladakh, the Chinese were now eyeing a repeat in the eastern sector.

In an interview to journalist Karan Thapar for The Wire news portal, a former colonel, Ajai Shukla, said the Chinese action in Arunachal was more serious than what the government had given out so far.

A former major general expressed shock that the Centre had remained silent for three days on the intrusion bid, with “anonymous” government sources confirming it only on Monday evening after the media began reporting the matter.

Of the 3,488km Line of Actual Control, an undemarcated border, a stretch of 1,346km falls in the eastern sector. The Tawang sector has a 270km border with China. China lays claim to 90,000sqkm of Indian territory in the eastern sector, practically the whole of Arunachal.

“An internal assessment by security agencies suggests that the Chinese army has been making aggressive moves in Arunachal Pradesh and Sikkim over the past one year. They have been reinforcing their military posts closer to the frontier and deploying additional military assets,” a security official attached to the Union home ministry said.

“The latest incursion bid and their aggressive intent are very alarming,” the official said.

The Indian Army too has deployed additional troops in the eastern sector to deter Chinese incursions, a defence ministry official said. He said the army had installed additional cameras and was using satellite imagery to keep an eye on the deployment of Chinese troops along the LAC in the eastern sector.

In October last year, Indian and Chinese troops had been locked in a “faceoff” for a few hours in the Tawang sector after nearly 200 PLA soldiers had crossed over. The Chinese later returned to their side of the frontier following intervention from Indian Army commanders.