Danish intelligence warns of growing risk of limited Russian attack on NATO eastern flank
Denmark's Defence Intelligence Service published a threat assessment on September 24 warning that Russia is likely to intensify hybrid operations against Western countries and NATO in the coming months, including a "small but growing" risk of a limited military attack on a NATO country bordering Russia. The Danish Civil Security Agency subsequently raised its cyber threat level, and Denmark reaffirmed its continued support for Ukraine.
Key points
- Denmark's Defence Intelligence Service published the assessment on September 24.
- Head of Danish intelligence Thomas Ahrenkiel described the risk of a limited Russian military attack on a NATO eastern-flank country as "small but growing" but currently "low".
- Possible tactics named include long-range drone or missile strikes on infrastructure supporting Ukraine, "false flag" operations using Ukrainian-made drones, and deployment of Russian troops in neighbouring NATO countries without insignia.
- Denmark, which does not border Russia, is not considered a potential target.
- The Danish Civil Security Agency raised its threat level for "destructive cyber attacks" from medium to high, citing Russia's growing tendency toward hybrid attacks and specific information about planned sabotage actions against Denmark.
- Ahrenkiel said Russia's hybrid focus is on the defence industry, companies supporting Ukraine, obstructing aid deliveries to Kyiv, and possible attacks or sabotage against vehicles travelling to or from Ukraine.
- Estonia's Ministry of Defence said the Danish warning largely reflects its own assessment and does not require raising combat readiness, but that Estonia is "closely monitoring developments".
Why it matters
The assessment is a formal intelligence judgment by a NATO member state, not media speculation, and it identifies concrete hybrid tactics — sabotage, cyberattacks, attacks on the defence industry and aid supply chains, possible strikes or sabotage against vehicles travelling to or from Ukraine, and possible "false flag" operations using Ukrainian-made drones. The Danish Civil Security Agency backed the assessment operationally by raising its cyber threat level and citing information about planned sabotage actions against Denmark. Denmark simultaneously reaffirmed its continued support for Ukraine, signalling that the heightened threat is not expected to alter its policy. Estonia's response indicates that the Danish view aligns with the assessments of other NATO eastern-flank allies.
What happened
On September 24, Denmark's Defence Intelligence Service released a new threat assessment warning that Russia is likely to intensify its hybrid warfare against Western countries and NATO in the coming months, with more frequent attacks and more serious consequences. Head of Danish intelligence Thomas Ahrenkiel stated there is a "small but growing" risk of a limited military attack against a NATO country on the eastern flank bordering Russia, though the current risk is assessed as "low" and no signs of a direct invasion of a NATO member state are visible. According to the assessment, a limited Russian operation could take the form of long-range drone or missile strikes on infrastructure critical to supporting Ukraine, "false flag" operations using Ukrainian-made drones, or the deployment of a small number of Russian troops in neighbouring NATO countries, possibly without national insignia. Ahrenkiel specified that Denmark, which does not border Russia, is not considered a potential target.
Following the intelligence assessment, Denmark's Civil Security Agency raised its threat level for "destructive cyber attacks" from medium to high, stating it considers it likely that Russia will attempt such attacks against Denmark and that it has information about specific plans for sabotage actions in the country. Danish Defence Minister Troels Lund Poulsen told a press conference in Copenhagen that the security situation is more serious than at any time since the end of the Cold War, and added that Denmark does not intend to stop its support for Ukraine. Estonia's Ministry of Defence said the Danish warning largely reflects its own assessment, that the situation does not require raising the combat readiness of its armed forces, and that Estonia is "closely monitoring developments" and "ready to take decisive measures" if necessary.
Where reporting differs
The Danish defence minister is named differently across the source material: some sources name him as Troels Lund Poulsen, others as Jeppe Bruus, and one source lists "Troels Lund Poulsen (Jeppe Bruus)". The role (defence minister) and the substance of his statements are otherwise identical.
Background
The Danish assessment comes against a backdrop of escalating Russian-linked incidents in Europe. On September 23, a Russian military helicopter violated Polish airspace near Braniewo, flying from the direction of Kaliningrad Oblast before turning back. In early September 2025, a Russian military ship fired signal flares toward a Danish military helicopter in the Baltic Sea, prompting Denmark to summon the Russian ambassador — an incident Danish Prime Minister Mette Frederiksen described as part of a trend of escalating Russian aggression. On September 18, Polish Prime Minister Donald Tusk said the most likely scenario for the coming months is Russian hybrid attacks using drones and missiles on Ukraine-supporting countries, with strikes possibly officially attributed to accident. The Wall Street Journal reported on August 6 that US intelligence considers it possible Putin may test NATO's readiness through cyberattacks, sabotage, or a limited invasion between autumn 2025 and 2029. CNN reported on September 17 that Russia's hybrid campaign aims to make the costs of supporting Ukraine feel increasingly burdensome to European publics and to test NATO's willingness to invoke Article 5. Germany accused Moscow of a failed drone attack at Leipzig airport in August. On June 28, the head of Poland's Foreign Intelligence Agency stated Russia is ready to send "little green men" into the Baltic states; Lithuania's Ministry of Defence said the next day there are currently no objective signs of a full-scale Russian attack on the Baltic countries.