Flight operations at the Calcutta airport were suspended from 7pm on Thursday because of Cyclone Dana. Flights are scheduled to operate again from 9am on Friday.

The prediction of strong crosswinds up to 80km an hour led to the shutdown.

As many as 309 flights were cancelled — 281 domestic and 28 international. Around 400 overflying flights were diverted on Thursday as a precaution against the cyclone, said airport sources.

Initially, it was decided that the last flight would take off at 6pm. But false security threats to 11 flights led to an hour’s delay in shutting down the airport.

IndiGo’s flight to Guwahati was the last to take off on Thursday evening, said an airport official. It left at 7pm. The last one to arrive was IndiGo’s flight from Amritsar, which touched down at 6.11pm.

“Although operations were suspended, the airport is not closed. Air traffic control personnel, ground staff, maintenance workers and engineers, along with some employees of airlines, will be at the airport during the period flight operations are suspended,” an official at the airport said.

According to sources, several overflying flights to and from southeast and far-east Asia were diverted.

The departure level of the terminal building started emptying out around 5.30pm. Around an hour later it was almost deserted.

Central Industrial Security Force personnel sealed the gates at the departure level by placing red tapes in front.

The passenger information board outside one of the gates for international fliers displayed that a Myanmar Airways flight to Yangon that was to leave at 6.35pm and an AirAsia flight to Bangkok that was to take off at 10.30pm had been cancelled.

The glass doors at the terminal were fortified with sandbags and plywood.

“All the aircraft were tethered to ensure they did not get dislodged by strong winds. Ground-handling equipment like ladders and tow bars have been tied together with chains. The combined weight of the items will make them stable against strong winds,” said the official.

The luggage trolleys, too, were tied with ropes. Many trolleys were taken inside the terminal building, while quite a few were kept tied together near exit gates 5A and 5B at the arrival level.

“Most of the trolleys were taken to the basement area,” said an official.

Inside the terminal, the airline counters were closed but a few employees were deployed to ensure the systems were running.

A large group of passengers from Imphal landed in the city around 4pm and were to board a flight to Delhi, which was to take off at 8pm.

“We are going to join a convention in front of Jantar Mantar in Delhi to highlight the plight of the people in Manipur, where a strife is on for 17 months now. However, we got to know that flight operations have been suspended. We are looking for a hotel,” said Iboyaima.

By 7.30pm, the arrival level had very few taxis, app cabs and cars. The food kiosks that were open had no customers. The only ones who could be spotted were people who work at the airport.