Coimbatore: High security alert continued in the district for the third day on Sunday, with places of worship especially churches being brought under heightened vigil in the wake of intelligence inputs on infiltration of LeT terrorists into Tamil Nadu. Three people taken into custody here on Saturday on suspicion of being in touch with a man detained in Kerala for alleged links with terrorists were released after questioning, police said. The trio was let off on the condition that it should appear before the police whenever required, they said. Also Read – India gets first tranche of Swiss bank a/c details Tight security measures including intensified vehicle and baggage checks continued across the city, where a high alert has been sounded since Friday following information that terrorists have entered the state and were heading here. The entire state is on alert with sensitive installations in places of large congregation coming under police vigil. Since the terrorists entered the country by sea from Sri Lanka, police suspected they may carry out attacks on places of worship, particularly churches, where a large number of faithful gather on Sunday, as was done in the island nation during the easter holiday. Security and anti-sabotage checks were carried out in major churches on Saturday night by commando force personnel, with assistance of sniffer dogs, police said. A three-tier security was in place at the international airport and over 2,000 police personnel were deployed in malls and places with large public concentrations in the city, they said.