A jackal strolling on Calcutta airport’s primary runway forced an aircraft to hover for 45 minutes before it could land and stalled the take-off of three flights on Wednesday afternoon.

The air traffic control was informed about the jackal by the pilot of an Agartala-Calcutta IndiGo flight, which touched down at 4.15pm.

“The ground control immediately suspended landing and take-off,” said an official.

Air India’s Silchar-Calcutta flight, with 100-odd passengers, was preparing to land around 4.30pm when it was asked to hover till the runway was declared safe. The flight finally landed at 5.15pm.

A Jet Airways flight to Agartala preparing to take off was asked to wait at the edge of the runway for around half an hour. The departure of the United Airways Calcutta-Dhaka flight and the Deccan Calcutta-Bangalore flight, too, was delayed.

Flight operations have often been disrupted at the city airport in the past few months because of jackals on the runway, resulting in wastage of precious air turbine fuel.

An Airbus A320 consumes fuel worth Rs 1.2 lakh if it hovers for 30 minutes.

Officials said 15-20 jackals loiter around the airport’s operation area. In July, forest department and airport officials decided to relocate the animals. “Forest officials conducted a number of surveys but nothing has changed,” said an airport official. Forest officials refused comment.