People familiar with the matter said there was fuel spillage from the right wing of the aircraft as it was taxiing for take-off. Then engines were then shut down and the plane was towed back to the parking bay at the airport for inspection by engineers. A firefighting truck was also kept on standby.
IndiGo on Wednesday said there was no "fuel leak" on the Thiruvananthapuram-bound flight. The no-frills airline in a statement said the aircraft's on-board computers detected fuel overflow, after which the flight crew carried out the procedure needed in such a scenario.
"On the 26th of December, 6E-945 (Delhi-Trivandrum) flight crew were alerted by on-board computers about 'Fuel Right Wing Tank Overflow'. Flight crew carried out their required procedure as per Airbus checklist and the overflow was confirmed by the ground staff," IndiGo said in the statement.
Airport sources told news agency Press Trust of India that the airline reported a "wing tank overflow" at first, and later it acknowledged oil spillage.
The airline, however, said, this "common occurrence and must not to be confused with a fuel leak". "Such overflows can occasionally be noticed during aircraft turns on ground with the fuel tanks full," IndiGo said in the statement.
IndiGo later arranged another plane for the passengers; the flight took off two hours after the incident and landed safely at Thiruvananthapuram.
IndiGo said it has informed the aviation regulator DGCA, and the private airline's safety department is looking into the matter.
With input from agencies