However, "on arrival", the passenger was declared dead by the "airport medical team", IndiGo said in a statement on Monday.

"IndiGo flight 6E-57, operating from Bangkok to Mumbai was diverted to Rangoon due to a medical emergency on board. Unfortunately, on arrival, the passenger was declared dead by the airport medical team," the airline said in a brief statement.

The IndiGo flight 6E-57 had to be diverted owing to a medical emergency only minutes after the flight took off.

According to the airline, the passengers suffered a heart attack on board less than an hour after the flight took off from Bangkok at 4 PM (local time).

After nearly five hours of wait, the flight took off from the airport in Yangon, Myanmar.