The 4056-kilometre border between India and China runs through glaciers, snow deserts and rivers in the west to thickly forested mountains in the east.
The Galwan Valley is an arid, inhospitable area, where some soldiers are deployed on steep ridges. It is considered important because it leads to the Aksai Chin, a disputed plateau claimed by India but controlled by China.
The satellite pictures, taken by Earth-imaging company Planet Labs, show signs of altering the landscape of the valley through widening tracks, moving earth and making river crossings, one expert said.
The images shows machinery along the bald mountains and in the Galwan River.
“Looking at it in Planet, it looks like China is constructing roads in the valley and possibly damming the river,” Jeffrey Lewis, director of the East Asia Nonproliferation Program at California’s Middlebury Institute of International Studies.
“There are a ton of vehicles on both sides [of the LAC],- although there appear to be vastly more on the Chinese side. I count 30-40 Indian vehicles and well over 100 vehicles on the Chinese side.”
Chinese Foreign Ministry spokesman Zhao Lijian said he was unaware of the specifics on the ground but reiterated that the Indian army had crossed into Chinese territory in several places in recent days and that they should withdraw.
The clash was the most serious since 1967. Since early May, soldiers have faced off on the border where India says Chinese troops had intruded and set up temporary structures. The confrontation turned into a deadly brawl on Monday.
The fighting was triggered by a row over two Chinese tents and observation towers that India said had been built on its side of the LAC, Indian government sources in New Delhi and on the Indian side of the border in the Ladakh region said.
China had sought to erect a “structure” in the Galwan Valley on India’s side of the LAC even after military officials had reached an agreement on June 6 to de-escalate, Indian Foreign Minister Subrahmanyam Jaishankar told China’s senior diplomat, Wang Yi, in a phone call on Wednesday, the Indian Foreign Ministry said. It was not immediately clear to what structure he was referring.
The problem arose when an Indian patrol visited the area near a ridge to verify a Chinese assertion that its troops had moved back from the LAC, the two government sources aware of the military situation said.
The Chinese troops had thinned out and left behind the two tents and small observation posts. The Indian party demolished the towers and burnt the tents, the sources said.
The satellite images show possible debris from the observation posts on Tuesday morning on a ridge on India’s side of the LAC. There was no such structure in the image taken a week earlier.
A large group of Chinese soldiers arrived and confronted the Indian troops, led by Colonel Santosh Babu. They were lightly armed in line with the rules of engagement at the LAC, one of the sources said.
India and China have not exchanged gunfire at the border since 1967, despite occasional flare-ups. Soldiers are under instructions to keep their rifles slung at their backs.
It was not clear what happened next, but the two sides soon clashed, with the Chinese using iron rods and batons with spikes, one of the sources said.
Colonel Babu was one of the 20 victims, they said. More Indian troops were rushed in and the confrontation turned into an hours-long brawl eventually involving up to 900 soldiers, the source said. Still no shots were fired on either side.
Emotions were high in the southern city of Hyderabad, where thousands watched Babu’s funeral procession.
An Indian business confederation called for a boycott of 500 Chinese goods, including toys and textiles, to express “strong criticism” of China’s alleged aggression in Ladakh.
Chinese Foreign Ministry spokesman Zhao rejected the Indian version of the events. “The rights and wrongs of this incident are very clear. The responsibility does not lie with China.”
Experts have said the two nations were unlikely to head to war, but that easing tensions quickly would be difficult.
China claims about 90,000 square kilometres of territory in India’s northeast, while India says China occupies 38,000 square kilometres of its territory in the Aksai Chin Plateau in the Himalayas, a contiguous part of the Ladakh region.