Flights have been suspended at Copenhagen airport in Denmark after reports of drones in the air.

Denmark‘s biggest airport was forced to close on Monday evening following the sightings.

Police said two or three large drones had been seen flying in the area.

The airport halted operations at 8.26pm local time (7.26pm UK time) according to flight tracking service FlightRadar.

Around 35 flights were diverted to alternate airports, FlightRadar said.

An airport spokesperson said police were working to identify the drones but declined to provide further details, citing the ongoing investigation.

It is not yet clear how long the airport will remain closed for. There are also no details on where the drones may have come from.

Sky News presenter Jonathan Samuels, who is at Copenhagen airport, said passengers have been stuck on aircraft about to take off, while others were in the terminal with limited information about when the airport might reopen.

Passenger Louise McFadzean said she was waiting at the gate about to board a flight to Heathrow when she suddenly “saw blue lights on the runway”.

“We were told the plane we were due to get had been diverted to Sweden,” she added.

“It’s quite scary and I don’t know when I’m going to get home.”

Images showed police patrolling the airport. According to local media, the airport will either wait for the airspace to reopen, deploy buses or find accommodation for passengers.

It comes after disruption at Heathrow Airport last week following a cyber attack that also hit other major airports in Europe.

The cyber attack targeted a service provider for check-in and boarding systems.

The “technical issue” that hit Collins Aerospace resulted in 14 flights being cancelled at Brussels Airport on Saturday and several more at Heathrow, Berlin, Dublin and others.

Passengers complained they were unable to check in online, instead queuing for hours for staff to deal with them manually at desks and departure gates, where they were told their flights would not be taking off.