Passengers were unhurt, said a source. The pilot of the A320 Neo plane issued a 'May Day' call to seek help and some of the passengers were evacuated using emergency chutes on landing.
"The IndiGo aircraft VT ITR was about 45 miles (around 72 km) off Kolkata when the smoke engulfed the aircraft. Amid the passengers' safety in danger, the pilot issued May Day and sought an emergency landing at the Kolkata airport," the source said.
"An IndiGo flight (A320 aircraft) 6E-237 operating on Jaipur-Kolkata route made an emergency landing as a precaution at Kolkata due to suspected smoke in cabin,"

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