OSLO - Denmark's Aalborg Airport shut its airspace late Wednesday after drones were observed near the facility, prompting the diversion of several inbound flights, according to local police.

North Jutland Police said on X that "drones have been observed in the vicinity of Aalborg Airport and the airspace is closed," adding that officers are on site to investigate.

Authorities have not announced suspects or a motive in the incident, and the investigation is ongoing.

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Flight-tracking service Flightradar24 said three arriving flights had been diverted to other airports after the shutdown.

The incident comes amid heightened concern over drone activity in Scandinavian airspace this week. On Monday evening, Copenhagen Kastrup Airport was closed for four hours after multiple drone sightings, disrupting scores of flights, while Norwegian authorities temporarily halted operations in Oslo Gardermoen Airport on Tuesday morning for three hours.

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In response, Danish Prime Minister Mette Frederiksen said the incident in Copenhagen Airport was "a serious attack on Danish critical infrastructure." The incident should be viewed within the broader context of hybrid threats across Europe, she added.