India, May 13 -- The Netaji Subhas Chandra Bose International Airport in Kolkata was put on high alert on Tuesday afternoon, and passengers who had boarded the Kolkata-Mumbai IndiGo flight No 6E5227 were taken to safety, after an unidentified person called the airport claiming there was a bomb on the plane, officials said.

"The call came after the passengers had checked in. The flight was scheduled to take off at 1.30pm and land in Mumbai at 4.20pm. All 195 passengers were asked to deplane following emergency protocol and the aircraft was taken to the isolation bay," an airport official said requesting anonymity.

"Luggages have been unloaded from the aircraft. Bomb squad personnel are on board. They are scanning the aircraft. The Centra...