It could be a new camouflage overall or it could also be an indigenous way of wearing a wet-sack like clothing to evade the HHTI radar.
Security agencies have flagged a new strategy of Pakistani personnel wearing 'thermal camouflage suits' to avoid detection by Indian night vision devices, a design adopted by them to kill a BSF Jawan along the border in Jammu and Kashmir amid the recent spate of ceasefire violations.
The "disturbing" first-time instance, officials told PTI quoting an electronic surveillance report, has rattled the top commanders responsible for ensuring security at the Indo-Pak IB and the un-fenced Line of Control in Jammu and Kashmir.
Constable Sitaram Yadav (28) of the 192nd battalion of the Border Security Force, manning a forward post along the IB in the RS Pora region, was shot with a precise close-range aim by either a militant or Special Service Group (SSG) trooper from the Pakistani side at about 1:30 am on May 18, they said.
Official sources said a grievously injured Yadav was immediately evacuated by two other BSF Jawans present in the nearby post but he later succumbed to his bullet wound that he took in his left eye.
The BSF commanders initially thought that the jawan was killed by a sniper shot from across the border.
However, a threadbare scrutiny of the local hand-held thermal imager (HHTI) showed that a very-grained black shadow like movement takes place on the monitor and it comes very close to the BSF post and fires a shot, that is suspected to have hit the jawan leading to his killing, they said.
The worry is that the HHTI, deployed in the border areas for night vision and surveillance, could not clearly pick the black shadow of an approaching man as he might be wearing a 'thermal camouflage suit' that insulates the body heat of a person, they said.
The HHTI picks up the body heat signatures of a living being -- a human or an animal -- and creates a silhouette that helps the BSF and the Army to check infiltration bids and attacks on their posts in the dead of the night.
"The electronic surveillance of the incident is being analysed and nothing can be ruled out.
It could be a new camouflage overall that the Pakistani side is using to take a close aim and hit Indian troops at the border or it could also be an indigenous way of wearing a wet-sack like clothing to evade the HHTI radar," a senior officer in the security establishment said.
He added that this "menacing stealth operation"-- carried out either by militants, the SSG or Pak regulars -- is a worrying development on the volatile and sensitive border and is being investigated thoroughly.
There are such thermal camouflage or insulation suits available across the globe that are used for such tactical and surprise attacks on the enemy and before anything is conclusively said, all aspects of this latest development have to be studied as it concerns border security, he officer said.