The suspect has been identified as a native of Thrissur district in Kerala who was reportedly employed in Bahrain and later remained elusive.
Sources claimed that the suspect is believed to be carrier for the six LeT men about whom the alert was issued.
As per the intelligence input, the six men entered Tamil Nadu via Sri Lanka.
Of the six men, one is a Pakistan national and the others are Tamil Muslims from Sri Lanka. The Pakistani has been identified as Illyas Anwar. The intelligence alert said that the men were in disguise as Hindus with vibhuti or tilak smeared on their foreheads.
Following the intelligence input, high alert was issued in Coimbatore late on Thursday.
From midnight, police presence was evident in important places in the city. Security cover for places of religious importance was enhanced while leaders of pro-Hindu outfits were informed about the alert. The police also checked vehicles at several places.
Taking stock of the security situation, Additional Director General of Police (Law and order) Jayanth Murali held discussions with senior police officers in Coimbatore early on Friday.
In Coimbatore city, police have deployed 1,300 personnel as part of heightened security. The security cover in places like railway stations, bus stands and airport was also beefed up. Around 8,000 police personnel have been deployed in the eight districts in the western region.