Danish authorities are investigating coordinated drone incidents that disrupted operations at multiple airports across the country, with police suspecting a connection between the activities in Aalborg and Copenhagen. The incidents, which occurred over several days, prompted temporary closures of airspace and raised concerns about national security. At least five Danish airports reported drone sightings, leading to significant flight disruptions and operational challenges for aviation authorities.

The drone activity began on Wednesday evening near Aalborg Airport, forcing the suspension of all air traffic. On Thursday morning, Billund Airport, Denmark's second-largest airport, was forced to close its airspace for one hour. Police Inspector Henrik Skals of North Jutland Police confirmed that the drone activity in Aalborg resembled the incidents that halted air traffic to and from Copenhagen earlier in the week, indicating a potential coordinated operation.

Defense Minister Troels Lund Poulsen characterized the events as a "systematic operation that occurred simultaneously" during a Thursday morning press conference. He described the incidents as a "hybrid attack that threatens our freedom and security," suggesting that a professional actor was behind the coordinated disruptions. Foreign Minister Lars Løkke Rasmussen urged citizens not to be intimidated, stating "the purpose is to scare us. We should not fall for that. So therefore: Stay calm and carry on."

Authorities have launched a joint investigation between Copenhagen and Aalborg, with a press conference scheduled for 7:30 PM Thursday involving the National Police, the Defense Forces, and other agencies. Police Chief Thorkild Fogde noted that the origin of the drones remains unclear, stating they "could have come from far away or from very close by" and that no hypothesis has been established. While maritime traffic has been considered in the investigation, Fogde explained that authorities lack sufficient grounds to board foreign vessels in Danish waters without concrete suspicion.

Finnair is gradually restoring its Airbus A321 fleet to service after an uncertified cleaning procedure forced the grounding of eight aircraft. The airline confirmed that seat covers were washed with water, a method not properly certified to ensure fire protection standards were maintained. This safety concern prompted the removal of the affected aircraft from service, leading to operational disruptions across Finnair's European network.

The situation began improving over the weekend as Finnair started installing new seat covers on the grounded aircraft. The first A321 returned to service on Sunday, operating a flight from Helsinki to Rhodes. However, seven aircraft remain out of service with no confirmed timeline for their full return. The A321s typically seat approximately 200 passengers and are crucial for Finnair's European route operations.

The grounding has resulted in significant passenger disruptions, with Finnair implementing extensive rebooking procedures. On Sunday alone, approximately 460 passengers were moved to different flights due to aircraft downgrades. The airline has prioritized high-frequency routes such as Helsinki-Stockholm and Helsinki-London, ensuring alternative options are available. In some cases, Finnair has used smaller replacement aircraft and offered incentives for volunteers to switch flights.

To manage the capacity shortfall, Finnair has wet-leased two aircraft with crews from Danish carrier DAT since Wednesday. While flight cancellations have decreased to single digits in recent days, with some days passing without any cancellations, the airline acknowledges that irregularities may continue through the coming week. Finnair is providing accommodation and compensation to affected passengers in accordance with EU air passenger rights regulations as it works to fully resolve the operational challenges.