The verdict, delivered on Thursday, marks NIA's first conviction involving PFI operatives since the organisation was banned by the central government.
The murder occurred on 22 September 2016 in Coimbatore when Sasikumar was hacked to death in front of a crowd, prompting widespread violence across six districts and triggering over 300 FIRs.
Investigations traced the killing to a premeditated conspiracy by PFI members, leading to a charge sheet filed in January 2018 and a trial that began in 2019 with 75 prosecution witnesses.
During the trial, the prosecution secured convictions under IPC sections 302, 120-B and 153-A, as well as UAPA sections 16, 18 and 20, while one co‑accused, Abu alias Syed Abuthagir, was acquitted.
NIA now plans to appeal the acquittal, exploring all legal avenues, while state authorities continue to monitor the case for potential communal fallout.