Danish airports affected by drone sightings 

Aalborg airport in Denmark was closed due to drones in its airspace overnight, according to local reports.

Three other smaller airports in the country’s southern region - Esbjerg, Sønderborg and Skrydstrup - also reported drone activity, but were not closed.

This came after the country’s main Copenhagen airport was shut on Monday over drone sightings.

At least three flights were diverted from Aalborg airport, with officials saying the Danish Armed Forces were affected as the airport is also used as a military base.

Authorities in Norway also shut the airspace at Oslo airport for three hours on Monday evening after a drone was seen.

Danish national police said the drones followed a similar pattern to the ones that had halted flights at Copenhagen airport for four hours a few days earlier. 

Local police later said the drones had left the Aalborg area after about three hours, Reuters reported.