After takeoff, the crew got an alarm and declared a full emergency. Later, the flight landed safely in Chennai at 134 am.
However, on inspection, it turned out to be a false alarm.
According to a press release by the airline, "IndiGo A320 was operating Chennai-Kuwait 6E-1751. After take-off from Chennai, the pilot observed a momentary message of the smoke detector in the aft cargo compartment. As a precaution, the pilot returned to Chennai. After arrival, it was confirmed that the message was false. The aircraft will be back in operations shortly."
IndiGo made alternate arrangements for all the passengers.
The matter was reported to the Directorate General of Civil Aviation and an investigation is underway.