The People's Liberation Army (PLA) of China had carried out a scouting mission using a top quality aircraft equipped with Synthetic Aperture Radar (SAR) that enables broad-area imaging at high resolutions ahead of its transgression in Barahoti area in Uttarakhand.
Official sources have said that earlier this year, the 'TupolovTu 153M' aircraft of PLA executed two to three sorties in the middle sector falling in the areas of Uttar Pradesh, Himachal Pradesh and Uttarakhand.
Piecing together intelligence gathered from various sources in the aftermath of Barahoti transgression, officials in the know said that at least three sorties of the aircraft, which is designed by the Chinese companies on the basis of technology from the erstwhile USSR, was carried out in last three months.
The aircraft flies at an altitude of above 40,000 feet and can go up to 60,000 feet to avoid detection by radars and can click pictures and other cyber and communication signatures at that height.
It has an SAR which can provide high-resolution pictures even in inclement weather or in night time. The systems take advantage of the long-range propagation characteristics of radar signals and the complex information processing capability of modern digital electronics to provide high resolution imagery.
The information about the flight was shared during exchanges with foreign intelligence agencies, the sources said.
At least 20 to 25 Chinese troops had entered into the demilitarised area in Barahoti pastures in Chamoli district of Uttarakhand earlier this month, besides flying its helicopters in the Indian air space for over five minutes.
The sources said that an Indian civilian team was sent back by Chinese People's Liberation Army troops, who claimed it to be their land and recognised it as 'Wu-Je'.
A Chinese helicopter hovered over the ground for nearly five minutes before returning to its side. It was apprehended that it could have carried out aerial photography of the area during its reconnaissance mission. The chopper was identified as Zhiba series of attack helicopter of the PLA.
(With PTI inputs)