DIG (Police Control) Nepal Das said patrolling of Tripura State Rifles (TSR) and CRPF was intensified in hilly and insurgency-hit areas and the camps of the security forces were alerted.
A joint press statement issued by 12 insurgent outfits of the region, including National Liberation Front of Tripura (NLFT) and ULFA appealed to the people of the north eastern region to observe the Independence Day as Black Day.
Das said additional security forces were deployed to guard vital installations, including Raj Bhavan, state civil secretariat, residences of VIPs and crowded places in the state.
All vehicles entering the towns from outside were being checked and specially trained dogs and bomb squads were conducting searches.
The DIG said the BSF was alerted because the insurgents of the state who have their base camps in neighbouring Bangladesh might try to sneak into the state for subversive activities.