Ahead of the visit of Pakistani Special Investigating Team, likely to take place in the last week of this month, the NIA sent the Letters Rogatory, a legal document sent through the special court asking details about the phone numbers dialled by the four terrorists ahead of carrying out the strike at the airbase of the Indian Air Force on the intervening night of January 1 and 2.
In a related development, it appears that no terrorists were present at the airmen billet.
The elite National Security Guards had spent 48 hours clearing the area.
While the NIA is officially tightlipped on the issue and says that it is awaiting forensic report from Central Forensic Science Laboratory Chandigarh, sources privy to the development said that no human remains or ammunition have been found from the airmen billet which has been extensively searched by sleuths of the NIA and central intelligence agencies.
The initial input about the terrorists says they were only four in number which had been shared with the NSG and army units. However, even the Intelligence Bureau was in for a shock when the NSG, which was rattled by the death of its officer Lt Col Niranjan E K, claimed that there was gunfire from the billet and took another two days to clear it, the sources said.
In the meantime, the NIA, in its Letters Rogatory, have sought details about telephone numbers dialled by the terrorists before launching the attack.
The numbers are believed to be in the names of people connected with JeM, including Mullah Dadullah and Kashif Jaan. The numbers shared belong to the Pakistani telecom operators like Mobilink, Warid and Telenor.
The NIA has also sought details and picture of sons of Khayam Baber, whose son was a part of the suicide squad that carried out the attack.
Kashif Jaan, one of the key handlers of the attackers, had accompanied the terrorists till the border and returned to supervise the operations, the sources said.
The bodies of four terrorists have been preserved. Out of the four, two of them have been identified as Nasir and Salim.
Nasir was the one who had called his mother, Baber, in Bhawalpur from the phone snatched from jeweller friend of superintendent of police of Punjab Salwinder Singh.
The NIA has also given details including the batch number of food packets used by the terrorists after infiltrating into India on December 30. The terrorists had carefully buried the packets which had Pakistani markings and manufacturing dates of November and December 2015.
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