Unpacking Russian aircraft threat in NATO airspace
A number of incursions by unidentified drones across Denmark that caused the temporary shutdown of two airports and affected military installations were part of a "hybrid attack," the country's defense minister said Thursday. Police in neighboring Norway, meanwhile, said they had seized a drone near Oslo's airport, the AFP news agency reported, and police said more drone activity was reported in Denmark later on Thursday, according to local media.
A public prosecutor in Norway said Thursday that there was nothing to immediately suggest any link between the Oslo incident and the drones seen in Denmark, according to AFP.
While neither Danish nor Norwegian officials have accused anyone of responsibility, the incidents come with many European nations on alert following Russian drone and fighter jet incursions into Poland, Romania and Estonia.
At a press conference alongside Denmark's justice minister and police, Minister of Defense Troels Lund Poulsen said that what he called a "professional actor" had been responsible for the drone incursions in that country.
Poulsen said different types of drones had been spotted at various locations, including near critical infrastructure and military areas, and appeared to be part of a "systematic" attack carried out by a "professional actor." He did not give further details on what he meant by that term, or who he may have been referring to, but added that "there is still no direct military threat to Denmark."
Poulsen said Denmark was considering requesting consultations under NATO's Article 4, which allows member states to discuss issues of concern with the rest of the alliance. He noted that the country had already reached out to NATO and was planning to reach out to the European Union to discuss the drones.
He said there was no evidence that Russia was behind that attack.
A series of drone incursions in Denmark
On Wednesday, Denmark's second biggest airport, Billund, was closed for an hour, and another airport used for both commercial and military flights was closed for three hours, police said, citing drone sightings, according to local media and the Reuters news agency.
Unidentified drones were also seen overnight near two other airports and an air base, which is home to some of Denmark's F-35 and F-16 fighter jets, Reuters reported.
The national police said the drones followed similar patterns to others that halted flights for four hours at Copenhagen Airport earlier in the week, according to Reuters. After that incident, Jens Jespersen of the Copenhagen Police said the those responsible seemed to be showing off their skills, adding that the number, large size and flight patterns of the unidentified drones combined indicated "that it is a capable actor. Which capable actor, I do not know."

On Tuesday, in response to those earlier incidents, Denmark's Prime Minister Mette Frederiksen said she could "certainly not rule out in any way that it is Russia" behind the drone activity, calling it "the most serious attack on Danish critical infrastructure to date."
She said the motive of the attacks was likely, "the obvious: To disrupt and create unrest. To cause concern. To see how far you can go and test the limits," according to Politico.
Russia dismisses "unfounded accusations" over potential involvement
During a briefing Tuesday in Moscow, Kremlin spokesperson Dmitry Peskov dismissed allegations that Russia could be responsible for the drone incursions.
"Each time they make unfounded accusations, frankly, it leads to the continuation of such statements no longer being taken into account, because each time we hear unfounded accusations," Peskov said, according to Russia's state-run Interfax news agency. "Perhaps a country that takes a serious position should not make such unfounded accusations time and again."
Russia's embassy in Denmark, in a statement Thursday, said "incidents involving reported disruptions at Danish airports are a staged provocation. Undoubtedly, they will be used as a pretext for further escalating tension in the interests of forces seeking by all means to prolong the Ukrainian conflict and extend it to other countries."
"The Russian side firmly rejects the absurd speculations of involvement in the incidents," the embassy said.
Russian drones were detected in airspace over Poland and Romania this month, and three Russian fighter jets were intercepted in Estonian air space last Friday.
Denmark's justice minister, Peter Hummelgaard, said Thursday that "new capabilities to detect and neutralize drones must be acquired," and that the incursions into Demark's air space should be seen as "a long series of deeply worrying episodes across Europe," local media reported.
"The goal of these kinds of hybrid attacks is to create fear, create division and make us afraid," Hummelgaard said.
U.S. fighter jets were scrambled Wednesday, meanwhile, to identify and intercept four Russian warplanes flying near Alaska, the North American Aerospace Defense Command said. It was the latest in a series of Russian military flights in the Alaskan Air Defense Identification Zone, which is international airspace off the U.S. coast.
Haley Ott is the CBS News Digital international reporter, based in the CBS News London bureau.