The airspace over Aalborg Airport in Denmark has been closed after drones were spotted flying nearby, airport CEO Niels Hemmingsen told CNN on Wednesday.
At least three inbound flights have been redirected, while two outbound flights and one inbound have been canceled, according to FlightRadar24.
Police are investigating and have not yet determined who is controlling the drones or what their purpose is, Reuters reported.
This is the second time this week that an airport in Denmark has been forced to close due to drones.
On Monday, sightings of two or three large drones near Copenhagen airport halted all take-offs and landings for nearly four hours.
It’s unclear if the drones that flew near Aalborg Airport are the same as the ones in Copenhagen.
Denmark’s National Police Commissioner Thorkild Fogde told CNN Tuesday that they were not amateur or hobby drones, but rather large drones that likely had a capable operator, though police had not yet identified who was behind it.
In Norway, the airspace over Oslo Airport was closed for around three hours Tuesday morning due to a separate drone sighting. Fogde said there was no indication the Copenhagen incident was linked to the drone sighting in Oslo.
Europe has been on alert since Russian drones violated both Polish and Romanian airspace earlier this month – prompting NATO allies to pledge to beef up defenses on the bloc’s eastern flank.
This is a developing story and will be updated.
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