Some “readjustments” in deployment of troops were also carried out on the northern bank of the Pangong lake on the Indian side of the Line of Control (LAC) as part of precautionary measures, they said. The situation in the area was said to be sensitive.
The sources also said another round of military talks between the two sides on Wednesday to defuse tensions in the area remained inconclusive. The talks lasted nearly seven hours.
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The talks at the Brigade Commander-level on Monday and Tuesday also did not yield any tangible outcome, the sources said.
Sources said India has achieved tactical gains in eastern Ladakh in the last few days by occupying a number of strategically important hill tops and locations.
The enhanced deployment came in the wake of unsuccessful attempts by China to change the status quo in the region.
The two sides were earlier engaged in a confrontation on the northern bank of Pangong lake but it flared up for the first time on its southern bank, sources said.
At the military talks, the Chinese side conveyed its objection to India occupying certain strategic heights in the region, sources said.
But, the Indian delegation maintained that the heights are on the Indian side of the LAC, the sources added.
They said India wants to resolve the border row through talks, but at the same time it will effectively deal with any “misadventure” by China along the LAC.
In the wake of the Chinese attempts, the Indian Army has alerted all its frontline bases along the 3,400 km-long LAC to remain vigilant round the clock.
India had rushed in additional troops and weaponry to all sensitive border areas including in Arunachal Pradesh and Sikkim sectors after the Galwan Valley clashes which significantly escalated the tensions.
On Monday, the Indian Army said the Chinese military carried out “provocative military movements” to “unilaterally” change the status quo on the southern bank of Pangong lake on the intervening night of August 29 and 30 but the attempt was thwarted by the Indian troops.
External affairs ministry spokesperson Anurag Srivastava on Tuesday said the Chinese People’s Liberation Army (PLA) was engaged in “provocative action” again a day earlier when the ground commanders of the two sides were holding talks to ease the situation.
“The situation in the area remained sensitive,” said a source, adding India has significantly ramped up overall surveillance in the region.
In Beijing, Chinese foreign ministry spokesperson Hua Chunying alleged that the responsibility for the border tensions lies entirely with the Indian side.
“The responsibility lies entirely with the Indian side. China has exercised great restraint to avoid escalation,” Hua claimed at a media briefing in response to questions on the Sino-India border situation.
Defence minister Rajnath Singh on Tuesday carried out a comprehensive review of the situation in eastern Ladakh at a high-level meeting attended by external affairs minister S Jaishankar, National Security Advisor Ajit Doval, Chief of Defence Staff Gen Bipin Rawat, Army Chief Gen MM Naravane and Air Chief Marshal RKS Bhadauria.
At the nearly two-hour-long meeting, it was decided that the Indian Army will continue to maintain its aggressive posturing in all sensitive areas along the LAC to effectively deal with any Chinese “misadventure”, the sources said. A battalion of the Special Frontier Force was also deployed in the area.
The sources said the Indian Air Force (IAF) has also been told to enhance its surveillance on increasing Chinese air activities along the LAC in eastern Ladakh.
There have been reports that China has deployed J-20 long-range fighter jets and several other key assets in the strategically located Hotan airbase, which is around 310 km from eastern Ladakh.
In the last three months, the IAF deployed almost all its frontline fighter jets like Sukhoi 30 MKI, Jaguar and Mirage 2000 aircraft in the key frontier air bases in eastern Ladakh and elsewhere along the LAC.
The fresh attempt by China to change the status quo in the Pangong lake area is the first major incident in the area after the Galwan Valley clashes on June 15 in which 20 Indian Army personnel were killed. China also suffered casualties but is yet to make the details public. According to an American intelligence report it was 35.
India and China have held several rounds of military and diplomatic talks in the last two-and-half months but no significant headway was made for a resolution to the border standoff in eastern Ladakh.
Watch LAC row: India bolsters presence at strategic heights of Pangong lake area; military talks inconclusive