The agency's case is based on a National Investigation Agency complaint filed against the accused and Pakistan-based organisation Falah-i-Insaniyat Foundation.
The case posed unique challenges, such as a lot of evidence having blown to pieces in the suicide attack and seven accused being subsequently killed in encounters. However, the central agency used forensic tests including DNA profiling of the meagre evidence to breach the dead ends.
The 13,500-page chargesheet names Masood Azhar, his brothers -- Abdul Rauf and Ammar Alvi -- and his nephew Mohammed Umer Farooq, who had infiltrated into India in 2018 and was subsequently killed in one of the encounters in South Kashmir.
The case pertains to hatching a conspiracy, both on physical as well as cyberspace, for undertaking violent terrorist acts in Jammu and Kashmir and other parts of the country, by cadres of Pakistan-based proscribed terrorist organisations.
The NIA arrested Tariq Ahmed Shah and his daughter Insha Jan after investigation led to their house at Hakripora in Pulwama district of south Kashmir, where a video was filmed by Jaish-e-Mohammed terrorist Adil Ahmed Dar, who rammed an explosive-ridden car into the CRPF convoy. The video was released from Pakistan after the attack.
The probe into last year's Pulwama terror strike that left 40 Central Reserve Police Force personnel dead has virtually reached a dead end, with five persons, who were either conspirators or executers of the ghastly attack, being eliminated by security forces in various encounters. However, the case threw unique challenges for the National Investigation Agency, the anti-terror probe agency formed in the aftermath of the Mumbai terror strikes in 2008, as it there is no solid information about the perpetrators or the mastermind behind the attack.
Waiz-ul-Islam, 19, of Srinagar's Bagh-e-Mehtab locality and Mohammad Abbass Rather, 32, of Hakripora village in Pulwama district were arrested by the NIA, the official said.