Hybrid war is how Prime Minister Mette Frederiksen described Denmark’s security situation on Thursday evening, 25 September 2025, after drones disrupted airspace over several Danish airports.
Speaking to Danish broadcasters, she warned that “we have only seen the beginning” and identified Russia as Europe’s primary threat, while urging the public to remain calm as authorities strengthen anti‑drone capabilities.
What Frederiksen means by ‘hybrid war’
Frederiksen said a hybrid war is unfolding on Danish soil and across Europe: one day drones, another sabotage, then cyberattacks. The aim, she noted, is to create uncertainty and division rather than declare a conventional conflict. She cautioned against premature blame‑trading and called for giving the authorities space to do their work.
Drone incursions expose gaps around critical infrastructure
Between late Wednesday night and early Thursday, reports of drones led to temporary closures and heightened security at Aalborg and Billund airports, with additional sightings near Esbjerg, Sønderborg and the Skrydstrup air base.
According to police timelines, activity clustered between roughly 22:00 and 03:00 CEST, with Aalborg closed for several hours and Billund for about one hour. Earlier in the week, similar drone activity forced Copenhagen Airport to halt operations overnight.
Authorities have not disclosed the model or origin of the drones and have emphasized safety concerns when considering whether to neutralise them.
Russia named as Europe’s primary threat
While investigators have not publicly identified a perpetrator, Frederiksen said there is one country that constitutes Europe’s main threat: Russia. She placed the drone incidents within a broader pattern of hybrid attacks and sabotage across Europe and reiterated that Denmark would not accept attempts to destabilise its institutions or intimidate its population.
NATO coordination and the search for resilience
Frederiksen said Danish authorities are in close contact with NATO allies and neighbouring governments to detect and counter unmanned aerial systems. Ministers have signalled accelerated procurement of anti‑drone systems and the possibility of borrowing equipment to cover urgent gaps. Denmark is also examining whether to bring the issue to alliance fora and EU coordination on critical infrastructure protection.
Police caution and capacity gaps
Just hours before the prime minister’s interviews, police and defence chiefs held a press conference with a markedly more cautious tone. National Police Commissioner Thorkild Fogde said investigators “do not know who is behind” the incidents and outlined three investigative tracks: where the drones came from, how they operated, and where they disappeared to.
The head of the Danish Security and Intelligence Service (PET), Finn Borch, added that the pattern resembles hybrid warfare seen elsewhere in Europe but stressed there was no attribution at this stage. He also acknowledged insufficient counter‑UAS equipment, noting rapid innovation in drone tactics and the need to procure additional capabilities quickly.
From military intelligence (FE), Thomas Ahrenkiel observed that Russia has shown greater risk‑taking in using hybrid tools since the full‑scale war in Ukraine, while emphasising that authorities cannot yet name a perpetrator. The Chief of Defence, Michael Wiggers Hyldgaard, underlined a duty to down drones when safe, citing coordination between helicopters and police tactical units around Copenhagen during recent flyovers.
What remains unknown—and why it matters
Officials have not confirmed who controls the drones, how they were operated, or why the flights occurred at specific sites. It also remains unclear which technologies were used to evade detection and whether multiple platforms were coordinated.
These unknowns are central to Denmark’s next steps on rules of engagement, procurement, and legal authorities for neutralising drones around sensitive sites.
Implications for the Nordics and the EU
The incidents underscore the Nordics’ shared exposure to hybrid threats that blur domestic and external security. Coordinated NATO and EU responses—from information‑sharing to joint counter‑UAS standards—are likely to shape procurement choices, crisis protocols, and regional airspace security in the coming weeks.
