A suicide bomber of Jaish-e-Mohammed had attacked a CRPF convoy last February.
The National Investigation Agency's probe into last year's Pulwama terror attack, in which 40 CRPF soldiers were killed, has virtually reached a dead end with five people-who were either conspirators or executed the attack-being eliminated by security forces in encounters.
However, the case threw unique challenges for the NIA, the anti-terror probe agency formed in the aftermath of the Mumbai terror attack in 2008, as it there is no solid information about the perpetrators or the mastermind of the attack.
"It was a blind case for us. There were lot of murmurs but everything needs to be established beyond doubt in the court of law," a senior official, who is part of the probe, said.
The first challenge was to establish the owner of the car used by suicide bomber Adil Ahmed Dar. There was nothing available from the vehicle which carried the explosives. But with help of forensic methods and painstaking investigations, the serial number of the car that was blown into pieces beyond recognition was extracted and within no time the ownership of the vehicle was established.
However, the last owner of the car, Sajjad Bhat of Bijbehara from Anantnag district, had disappeared hours before the February 14 attack and joined Jaish-e-Mohammed, the terror group that carried out the attack. He was subsequently killed in an encounter in June last year.
"While it was clear that the suicide attacker was Adil Ahmed Dar, the same had to be established with evidence. After picking up human remains from various spots, it was sent for DNA profiling. The suicide attacker was identified and confirmed by matching the DNA extracted from the meagre car fragments with that of his father," the official, who requested anonymity, said.
The role of other conspirators which included Mudasir Ahmed Khan, Qari Mufti Yasser and Kamran came to light but all of them were killed in different encounters with security forces.
Mudasir Ahmed Khan was killed on March 10, Kamran on March 29, Sajjad Bhat on June 18 of last year while Qari yasser was shot in an encounter on January 25 this year.