Two helicopters belonging to People's Liberation Army of China hovered over Chamoli district in Uttarakhand on Saturday, which in turn triggered concern among India's security establishment about the PLA's fourth such incursion into Indian airspace since March 2017.
Official sources said the choppers, which returned to the Chinese side after about five minutes, could have carried out aerial photography of Indian ground troops during what was possibly a reconnaissance mission. The Indian Air Force (IAF) is probing the incident, an IAF source said.
The choppers were identified as the Zhiba series of attack helicopters. On previous occasions, Chinese helicopters had entered4.5 kilometres into Indian territory, an area that Chinaclaims as its own and recognises as Wu-Je.
State and army officials have been reviewing the security along the 350-kilometre border with Tibet after China's incursions into these areas, generally referred as the middle sector.
Barahoti is one of three border posts in the sector,comprising Uttar Pradesh, Himachal Pradesh and Uttarakhand,where ITBP jawans are not allowed to carry weapons and are incivilian clothes under a unilateral decision taken by the Central government in June 2000.
In 1958, India and China listed Barahoti, an 80-sq-kms loping pasture, as a disputed area where neither side would send their troops. In the 1962 India-China war, the PLA did not enter the 545-km middle sector, focusing on the Western(Ladakh) and Eastern (Arunachal Pradesh) sectors.
However, after the 1962 war, ITBP jawans patrolled thearea with weapons in a non-combative manner, under which thebarrel of the gun is positioned downward.
During prolonged negotiations on resolving border disputes, the Indian side had unilaterally decided in June2000 that ITBP troops would not be carrying arms to threeposts -- Barahoti, Kauril and Shipki in Himachal Pradesh.
Srikanth Kondapalli, Professor in Chinese Studies at theJawaharlal Nehru University, termed these transgression as"testing the nerves" of India and said "after violating theLine of Actual Control in the Western and Eastern sectors,Chinese troops now seem to be focusing on the middle sector.It's a cause of worry for us".
The professor said after the June 2000 informalagreement, India did abide by all conditions under the assumption that China would yield on the western or eastern sectors.
"But that didn't happen. Today the PAPF (People's ArmedParamilitary Force) and PLA are enforcing China's claimsthere," he said. Kondapalli referred to regional equations giving a Chinaa boost.
He recalled that Nepal and India had differences on the source of the Mahakali river and in the background of China's forays in Nepal as well as the latter joining the China-led One Belt One Road (OBOR) project, and said, "There have been some moves by the PLA to test us".
He said there had also been "a concerted effort" by thePLA "to test India" against the backdrop of the China Pakistan Economic Corridor (CPEC), a collection of infrastructure projects.
"So the latest intrusion is to test our nerves," he said. He even said China could deploy Unmanned Aerial Vehiclesin this region in "large numbers" to monitor Indian territory. "So the helicopter incident is a precursor," he said.
"A recce mission?" Security officials here felt that ahead of its transgression in the Barahoti area, the PLA could have conducted a reconnaissance mission using high class aircraft with Synthetic Aperture Radar (SAR), which provides broad-area imaging at high resolutions.
The officials said the PLA's 'TupolovTu 153M' aircraft had carried out two or three reconnaissance missions last year in the middle sector. They said there was a possibility that the same aircraft, designed by Chinese companies on the basis of technology obtained from the former Soviet Union, could have been usedthis year, too.
The aircraft flies at an altitude of above 40,000 feetand can go up to 60,000 feet to avoid detection by radars and can take photographs and cyber and communication signaturesfrom that height. SAR enables the taking of high-resolution pictures evenin inclement weather or in the dark.