Denmark’s Aalborg Airport, a dual-use facility that serves both civilian and military purposes, was temporarily closed due to unidentified drone sightings. The incident occurred on Wednesday at approximately 9:44pm local time, when multiple drones were spotted circling the airport with their lights on. Authorities reported similar sightings at other airports in Esbjerg, Sonderborg, and Skrydstrup, which is home to Denmark’s Fighter Wing and its fleet of F-16 and F-35 jets.

Despite efforts by the Danish armed forces and Northern Jutland police to monitor and identify the drones, their origin, purpose, and operator remain unknown. Officials have stated that it is too early to determine the goal of the drones or who is behind them. The drones eventually vanished without being intercepted.

This incident follows a similar disruption at Copenhagen Airport, the busiest in the Nordic region, which was forced to halt flights for four hours due to drone sightings. The Danish authorities have described the incident as a serious “attack” on the country’s infrastructure, although no culprit has been identified. Oslo Airport in Norway also experienced a brief closure due to a suspected drone sighting, prompting speculation about a potential wider campaign.

The Danish incidents are not isolated, as similar disruptions have been reported at other European airports. Major outages affected electronic check-in and boarding systems at London’s Heathrow, as well as airports in Berlin and Brussels, last weekend. British authorities detained a suspect in connection with a ransomware attack but later released him on conditional bail.

The wave of mysterious drone sightings in Denmark bears some resemblance to a similar series of incidents in the United States last year. Clusters of suspected unmanned aerial vehicles (UAVs) were reported in several states, prompting a joint federal-state task force investigation. However, the investigations ultimately concluded that most sightings involved authorized drones, misidentified manned aircraft, or other routine aerial and celestial objects.

The ongoing investigations into the Danish drone sightings have yet to yield any conclusive results. The authorities’ inability to identify the drones or their operators has raised concerns about the potential security implications of such incidents. As the situation continues to unfold, officials are working to determine the cause and scope of the disruptions, with the goal of preventing similar incidents in the future.