The agency identified the nabbed militant as Jemson Narzary (30), a resident of Dwsajora village of the district. He was arrested by the sleuths on June 16.
"The arrested NDFB(S) cadre was wanted in the case related to the mayhem that happened on December 23, 2014 (killing of Adivasis) at Lungsung area under Kokrajhar district of Assam," the agency said.
Narzary was later produced in a court which sent him to seven days of NIA custody, it said.