Chennai, Dec 3: Multi-tier security arrangements have been put in place across Tamil Nadu in view of the Babri Masjid Demolition anniversary on December 6.
Police sources here today said night vigil had been stepped up and check posts were installed in various parts of the state.
Vehicle checks had been intensified as all the vehicles entering the state and the city were subjected to thorough checking.
In night-long raids, that culminated this morning, police rounded up nearly 800 people as a precautionary measure.
Police personnel were deployed at various places, including temples, other places of worship, bus stands, shopping malls, railway stations and airport, where people congregate in large numbers.
Scanning machines were installed in Chennai Central and Egmore Railway stations. Patrolling have been intensified across the state and intensive checks were being carried out at various lodges to nab any anti-social elements staying there.
Sniffer dogs also have been pressed into service.
Officials said there was no let up in the security after the city police had been put on high alert a few days ago, following an e-mail threat received by a Delhi-based private television channel warning of terror attacks in some cities, including the city.
Similar multi-tier security had been put in place in Tiruchirapalli, Madurai and Coimbatore to prevent any untoward incident.