According to senior police officials, the two terrorists were apprehended from Laudangi in Batachipur near Arunachal Pradesh border under Dehkiajuli police station in Sonitpur district during wee hours.
The militants opened fire when the joint search team reached the spot after getting information of three NDFB(S) cadres hiding in the area.
Seeing the security forces, the insurgents opened fire on them, who retaliated to the attack, although there was no casualty.
While one militant managed to escape, police and army personnel nabbed two hardcore cadres.
The security forces have also recovered one 7.65 mm pistol, three live ammunitions, four mobile phones and two sim cards from the militants.
A joint search operation has been launched to nab the third cadre involved in the encounter.