The Chennai airport was put on high alert on Friday following a bomb threat to an airline.
The incident happened hours before Vice President M Venkaiah Naidu and Defence Minister Nirmala Sitharaman were scheduled to fly to the city later in the day.
An unidentified person called up the airline, which operates flights between Chennai and Hyderabad, and threatened to blow up flights. Twenty flights are scheduled between the two capital cities on Friday.
The Hyderabad airport too received a similar threat, a leading daily reported. Several other airports across the country have been put on alert following directions from the military intelligence, the news channel added.
Security was stepped up at the airport in view of Vice President Venkaiah Naidu and Defence Minister Nirmala Sitharaman's visit on Friday.