Drone flights the ‘most serious attack’ on Denmark’s infrastructure, says its PM

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Police officers stand guard after all traffic has been closed at the Copenhagen Airport due to drone reports in Copenhagen, Denmark September 22, 2025. Ritzau Scanpix/Steven Knap via REUTERS

Police officers standing guard after Copenhagen Airport was shut down following drone sightings in its airspace on Sept 22 in Denmark.

PHOTO: REUTERS

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Large drones flying over Copenhagen’s airport for hours and causing it to shut down constituted the “most serious attack on Danish critical infrastructure” to date, Prime Minister Mette Frederiksen said on Sept 23.

Airports in Denmark’s capital Copenhagen and Norway’s capital Oslo reopened early on Sept 23, hours after unidentified drones in their airspace caused dozens of flights to be diverted or cancelled, affecting thousands of passengers.

“This is part of the development we have recently observed with other drone attacks, airspace violations and

cyber attacks targeting European airports

,” Ms Frederiksen said in a statement provided to AFP.

She referred to similar drone incidents in Poland and Romania, and the violation by Russian fighter jets of Estonia’s airspace.

The governments of Poland, Estonia and Romania have pointed the finger at Moscow, which has brushed off the allegations.

Danish intelligence said the Scandinavian country is facing a “high threat of sabotage”.

Mr Flemming Drejer, director of operations at Denmark’s intelligence service PET, said at a news conference on Sept 23: “Someone may not necessarily want to attack us, but rather stress us out and see how we react.”

The police said that they had been unable to identify the drone operator.

Chief Inspector Jens Jespersen told reporters: “The number, size, flight patterns, time over the airport. All this together indicates that it is a capable actor. Which capable actor, I do not know.”

“It was an actor that had the capacity, the will and the tools to make their presence known,” he said, adding that “several large drones”

flew over the Copenhagen airport

for more than three hours late on Sept 22.

A heavy police presence was dispatched to investigate the drone activity, and the devices could be seen coming and going for several hours before flying away on their own.

The police were cooperating with the Danish military and intelligence service in their investigation, Chief Inspector Jespersen said.

The police decided not to shoot down the drones for safety reasons. “You have to think very carefully before starting to try to take down such big drones,” he said.

If they were to fall to the ground, “there are planes with people, fuel and also housing on several sides of the airport”, he pointed out.

Chief Inspector Jespersen said it was not known where the drones were being controlled from, but that it could have been from many kilometres away.

The drones were flying from several directions, he said.

“It could very well be something initiated from a ship,” he told Danish broadcaster DR.

The Copenhagen airport is located on the coast of the Oresund Strait, between Sweden and Denmark.

Airport officials said air traffic resumed early on Sept 23, but 20,000 passengers were affected by 31 flight diversions and more than 100 cancellations.

Heavy delays and disruptions were expected throughout Sept 23 as many planes were not at their planned airports.

The Copenhagen police said earlier they were also cooperating with colleagues in Oslo after drone sightings in the Norwegian capital also caused the airport to close for several hours.

“We had two different drone sightings,” Oslo airport spokeswoman Monica Fasting said.

“We reopened the airport around 3.15am (9.15am Singapore time),” she said.

A total of 14 flights were diverted from Oslo airport, she said.

Norway said on Sept 23 it may deport a Singaporean couple suspected of illegally flying a drone over Oslo.

They were arrested late on Sept 22 after a drone appeared over Oslo’s fortress and opera house in violation of a ban on flying over the centre of the capital.

The couple, who the police said were Singaporeans in their 50s and 60s, said they were both tourists visiting Norway.

“Since the two detained individuals are foreign nationals, it will be relevant to initiate a case for deportation or expulsion,” Norwegian prosecutor Andre Kvistad Alme said in an e-mail to Agence France-Presse.

“The case is at an early stage, but at this point, we have no reason to suspect that this incident is connected to the drone sightings at the Oslo or Copenhagen airports,” Mr Alme said.

“This matter will however be subject to further investigation including interrogations and technical examinations of the drone,” he added. AFP

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