"Debbarma was arrested during a combing operation at Raishyabari by Tripura State Rifles (TSR) on July 28 but his identity was revealed to the police during an interrogation yesterday," IG, Police Control, Nepal Das said.
He was remanded in police custody by a court in Kamalpur sub-division, he said.
"Debbarma is the second-in-command of NLFT (BM) group," Das told PTI.
The combing operation started after an insurgent of NLFT was killed at Raishyabari in an encounter with Tripura State Rifles (TSR) on July 22 and one Ak-47 rifle with 50 live cartridges were recovered from him, police said.