Monday night there was intense fighting between Chinese and Indian soldiers at a remote border in the Himalayas. India reported that 20 soldiers including one officer had been killed. China didn’t report numbers resulting from the skirmish but Indian reports claimed Chinese communication intercepts put the number of Chinese casualties at 43. No guns were used in the battle. Instead, combatants fought with rocks and fists. The Chinese reportedly used clubs made of wood and spiked with nails. Many of the soldiers appear to have died after falling from cliffs into a freezing river below.

Naturally in a situation like this there was disagreement over what sequence of events led up to the bloodshed. The NY Times and others reported that the conflict had been sparked by the recent construction of a new road to a remote air base by India. However that road is entirely on the Indian side of the so-called Line of Actual Control (LAC). Today, Reuters reports that satellite images of the area suggest a more specific cause for the fighting.

In the days leading up to the most violent border clash between India and China in decades, China brought in pieces of machinery, cut a trail into a Himalayan mountainside and may have even dammed a river, satellite pictures suggest…

The satellite pictures, taken by Earth-imaging company Planet Labs and obtained by Reuters, show signs of altering the landscape of the valley through widening tracks, moving earth and making river crossings, one expert said…

“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.”

But it appears it wasn’t just the new Chinese construction in general that set off the battle, it was the fact that China set up a temporary outpost on the Indian side of the LAC after an agreement to de-escalate the situation:

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.

You can see the satellite images for yourself here. Here’s a before and after comparison which appears to show debris from the observation post built by the Chinese.

When the Indian group burned the tents and observation post on their side of the LAC, a group of Chinese soldiers showed up and attacked them. According to AFP that set up a series of escalating confrontations. On Sunday of this week, the Chinese returned and threw stones at the Indian troops. Then on Monday fighting broke out on a ridge over the river.

Matters escalated rapidly and several Indian soldiers tumbled into the icy water, while an unarmed Indian patrol team led by Colonel Santosh Babu set out to parley with the Chinese.

But the Chinese refused to budge and attacked the Indians with boulders, rocks wrapped with barbed wire and clubs studded with nails, Indian reports said. Colonel Babu was seriously injured. He would later die.

Forty minutes later, the same unit led by a major returned and further fighting broke out, this time reportedly involving hundreds of soldiers and the Chinese outnumbering the Indians, raging until after midnight.

“When they [the Indian soldiers] were encountered by the Chinese soldiers they were overwhelmed and many were pushed down a harsh rocky slope,” one security source told AFP.

“They came hurtling down like free falling objects.”

So it sounds like it was the Chinese who instigated this fight by building on the Indian side of the LAC. Then when the Indian troops cleared the small outpost, the Chinese escalated the conflict by throwing stones. Naturally, China blames everything on India. Chinese Foreign Ministry spokesman Zhao Lijian said, “The rights and wrongs of this incident are very clear. The responsibility does not lie with China.”

Here’s a CBC report on the situation. The Canadian analyst in this report argues that there’s no way Chinese troops took this action (repeatedly attacking Indian troops) without approval from superiors. He says this was planned.