The hand-held thermal imagers (HHTI) with security forces failed to detect suspicious movement at the Line of Control (LoC). The Pakistani Special Forces team sneaked 250 metres across the Line of Control (LoC) along with at least team of 5-6 non state actors (Mujahideens) under the cover of darkness. The Army sources believe the trap was laid by the Pak's Border Action Team (BAT) sometime in midnight.
Sources also confirmed that Kirpan Post in Nangteki had HHTIs, which were used by the forces on the intervening night of 30 April-1st May.
They further said that in military terms it's given that there is not a complete success as far as HHTIs are concerned. Thermal imagers capture the body heat of any living being and produce an image on their monitors. The enemies often use thick cover of trees and big rocks to avoid possible detection. The Army also have passive binoculars with night visions, but even those, sources said had limited night vision "constraints".
The rest of the patrol team survived and hit back because of tactical training keeping a distance between them. Sources also said that since that was a day time attack (8:40 am), the chances are that the men hiding on the Indian side of LoC were wearing the Ghillie Suit -- perfect camouflage clothing designed to give cover to attackers.
Sources said camouflage clothing is used by Army or even by terrorist trying to resemble the background environment such as foliage or sand.
Once the attack was unleashed, the Pakistani Army continued to give cover fire pinning down the patrol team preventing them to rescue the two soldiers.