Denmark’s Aalborg airport, which serves both commercial and military flights, was closed early Thursday after drones were spotted in its airspace, police said, two days after Copenhagen airport experienced a similar disruption.Northern Jutland police said, “more than one drone was seen near Aalborg airport, flying with lights on,” Reuters reported. The drones were first detected at about 9:44 pm (1944 GMT) on Wednesday and remained in the area at the time of the press briefing early Thursday. Eurocontrol, which oversees European air traffic, said arrivals and departures at Aalborg would be at a “zero rate” until 0400 GMT due to the drone activity.The closure also affected Denmark’s armed forces, as Aalborg is used as a military base. The Danish military said it was assisting local and national police with the investigation but declined further comment. Southern Jutland police later noted on X that drones had also been observed near airports in Esberg, Sonderborg and Skrydstrup, home to Denmark’s F-16 and F-35 fighter jets.Danish national police said the drones followed a similar pattern to those that halted flights at Copenhagen airport for four hours on Monday. Authorities in Norway also closed Oslo airport for three hours Monday after a drone sighting. National police commissioner Thorkild Fogde said many drone reports had been filed since Monday, adding, “Of course many of these reports do not cover activities that are of interest to the police or the military, but some of them do, and I think the one in Aalborg does.”Police said it was too early to determine “what the goal of the drones is and who is the actor behind,” and added that they would take down the drones if possible. Investigators are working with the national intelligence service, the armed forces, and authorities in other countries. There is no danger to passengers at Aalborg airport or residents in the area, police said, and three flights had been diverted to other airports.Denmark called the Copenhagen airport incident “the most serious attack yet” on its critical infrastructure and linked it to suspected Russian drone incursions and other European disruptions. European Commission President Ursula von der Leyen said the drones were part of a “pattern of persistent contestation at our borders.” Russia’s ambassador to Denmark dismissed suspicions of Russian involvement in the Copenhagen incident as ungrounded. Norway’s foreign minister said authorities in the two countries are cooperating but have not established a connection between the events.(With inputs from Reuters)