Marking fourth such incident, two Zhiba helicopters of the Chinese People's Liberation Army (PLA) intruded into Indian airspace, hovering over the Chamoli district in Uttarakhand.
Official sources speculate that the helicopters may have been on a reconnaissance mission and could have aerially photographed Indian troops.
The incident is currently being probed by the Indian Air Force.
Let's learn more on PLA's intrusive strategies!
Where have the intrusions occurred?
There have been few instances of Chinese transgressions across the 350-km Indo-Tibetan border, which is part of the 545-km stretch called the middle sector, covering the states of Uttarakhand, Himachal Pradesh and UP.
During the Sino-Indian border negotiations, India had unilaterally decided that the Indo-Tibetan Border Police (ITBP), will not be carrying arms to the three posts in Uttarakhand including Barahoti, Kauril and Shipki.
Changing stances on the middle sector
Both countries mutually agreed to not send troops to Barahoti in 1958. China did not advance on this sector even during the 1962 war. Before India's decision in 2000, the ITBP patrolled the area with their gun barrels pointed downward, in a non-combative mode.
Aircraft & technology
Security forces speculate that PLA aircraft fitted with Synthetic Aperture Radar (SAR) enabling high resolution imaging have been employed for reconnaissance of the middle sector.
While PLA's TupolovTu 153M aircraft had also been used a couple of times last year, the Chinese version of the same aircraft fitted with Russian imaging technology and excellent radar- evading capabilities may also have been used.
What do these transgressions signify?
According to Prof. Srikanth Kondapalli, Professor of Chinese Studies at JNU, China is focusing on the Middle sector, after pushing-in on the Eastern and Western fronts.
He adds that the transgressions are intended to enforce Chinese claims and 'test India's nerves'.
Warning that the helicopter incident is to be treated as a precursor, he adds that China could deploy drones to monitor the Indian-side.