Security at Chennai airport was tightened on Thursday following a telephone call received in Kolkata, warning of bomb blasts at airports in southern states.
According to sources, an anonymous call was received by airport officials at Kolkata, who in turn alerted their Chennai counterparts.
The security was tightened ahead of the scheduled visit of Chilean President Michelle in Chennai on Thursday evening.
Besides increased security, frisking of passengers was also intensified, the sources said.
President Prathibha Patil is scheduled to arrive in Chennai tomorrow to participate in official engagements on Saturday.