LUCKNOW, May 1 -- An IndiGo flight bound for Raipur aborted its take-off at Lucknow airport after a group of monkeys was spotted crossing the runway, airport sources said on Friday.

According to airport sources, flight 6E 6521 with around 150 passengers on board had begun its take-off roll and was about 20-30 per cent down the runway at around 9 am on Thursday when the pilots noticed monkeys moving across.

The pilots immediately aborted the take-off and informed air traffic control, following which the aircraft returned and later departed after refuelling, about an hour later.

A significant amount of fuel was consumed during the aborted take-off, necessitating refuelling and causing delays to the flight as well as affecting the departu...