Chandigarh, Oct. 5 -- The National Investigation Agency (NIA) has filed a supplementary chargesheet against a key accused in the Sector-10 grenade attack case, allegedly masterminded by Pakistan-based Babbar Khalsa International (BKI) terrorist Harwinder Singh alias Rinda and US-based gangster Happy Passia. A Punjab resident, Abhijot Singh alias Babba alias Gopi, who was arrested in April 2025, has been identified as a co-conspirator and chargeesheeted before the NIA court. Two others, Rohan Masih and Vishal Masih alias Shalu, have already been chargesheeted while Rinda and Passia, who were behind the recruitment, funding, and supply of weapons, have been declared absconders in the case. According to the NIA, the target of the attack was a retired Punjab Police officer. The grenade used in the crime - an HG-84 - was manufactured in Pakistan. Probes revealed that Abhijot had travelled to Armenia in December 2023, where he came in contact with Shamsher Shera, a key aide of Passia. Shera recruited him into Passia's gang. After returning to India in mid-2024, Abhijot conducted a recce of the target in July 2024. The following month, he and Rohan attempted to eliminate the retired officer. As per the available details, acting on Passia's directions, Abhijot arranged a stolen motorcycle with a fake number plate for use in the attack. Passia also provided pistols to Abhijot and Rohan in August 2024. Eventually, Rohan and Vishal carried out the grenade attack on September 11, 2024, before fleeing in an auto-rickshaw. The Chandigarh Police initially arrested Kuldeep, an auto driver, in the case. However, since a chargesheet was not filed against him within the stipulated 180 days, the court released him on bail. While the retired officer had already vacated the house, preventing loss of life, the incident exposed the international terror links. The case was later transferred from Chandigarh Police to the NIA by the central government....