Volkswacht Bodensee - Drone flights 'most serious attack' on Danish infrastructure, PM says

Airports in Copenhagen and Oslo reopened early Tuesday, hours after unidentified drones in their airspace caused dozens of flights to be diverted or cancelled, disrupting thousands of passengers.

"This is part of the development we have recently observed with other drone attacks, airspace violations, and cyberattacks targeting European airports," 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.

Frederiksen told Danish broadcaster DR she could "not rule out" that Russia was behind the drone activity.

Moscow denied involvement, with Kremlin spokesman Dmitry Peskov criticising her remarks as "unfounded accusations".

On X, Ukrainian President Volodymyr Zelensky denounced what he said was a Russian violation of Denmark's airspace.

Danish police meanwhile said they had been unable to identify the drone operator.

"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," Copenhagen police inspector Jens Jespersen told reporters.

"It was an actor that had the capacity, the will and the tools to make their presence known," he said.

- 'High threat of sabotage' -

Danish intelligence said the Scandinavian country was facing a "high threat of sabotage".

"Someone may not necessarily want to attack us, but rather stress us out and see how we react," Flemming Drejer, director of operations at Denmark's intelligence service PET, said.

Jespersen said "several large drones" flew over the Copenhagen airport for more than three hours on Monday evening.

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

Police were cooperating with the Danish military and intelligence service in their investigation, Jespersen said.

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," Jespersen said.

If they were to fall to the ground, "there are planes with people, fuel, and also housing on several sides of the airport."

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 DR.

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

- Air traffic disruptions -

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

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

Long queues of passengers stood at counters at Copenhagen airport trying to rebook their flights.

"I'm not afraid ... but I am aware that Russia's hybrid war is expanding steadily," German traveller Eckart Nikolai Bierduempel told AFP.

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

"We had two different drone sightings," Oslo airport spokeswoman Monica Fasting told AFP.

"We reopened the airport around 3:15 am (0115 GMT)," she said.

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

Norway's government on Tuesday said Russia had violated its airspace three times this year, in April, July and August.

Police have yet to comment on the incident, but the country's intelligence service PST confirmed its involvement in the investigation.

Separately, a Singaporean couple in their 50s and 60s was arrested late Monday suspected of illegally flying a drone in central Oslo.

"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 Oslo or Copenhagen airports," prosecutor Andre Kvistad Alme said.

L.Meier--VB