Denmark has banned all civilian drone flights in its airspace this week as the country gets ready to host major European summits in Copenhagen.
The decision by the Danish transportation ministry to prohibit drones from today until Friday, 3 October, comes after drone sightings forced several airports in Denmark to shut last week.
It also follows drone sightings at several military facilities overnight into Sunday, as well as NATO's recent announcement that it would enhance its vigilance in the Baltic Sea region.
Denmark is due to host EU leaders on Wednesday, followed by a summit on Thursday of the wider, 47-member European Political Community - which includes the UK - and has already said it has increased security around the events after the drone incursions.
Swedish Prime Minister Ulf Kristersson said in a post on X that Sweden will send technology to counter unmanned aircraft systems and that his country separately on Sunday had also shipped "a handful" of radar systems to Denmark.
France will also be contributing to Denmark's anti-drone capabilities, said the French armed forces ministry on Monday.
The French government said it would be helping out Denmark via the use of a Fennec helicopter, as well as a team of 35 staff who would handle aspects of anti-drone work.
"We are currently in a difficult security situation, and we must ensure the best possible working conditions for the armed forces and the police when they are responsible for security during the EU summit," Danish defence minister Troels Lund Poulsen said in a statement on Sunday.
Earlier, on Sunday afternoon, the Danish defence ministry announced that Germany's air defence frigate, FSG Hamburg, had arrived in Copenhagen.
"The ship will contribute to strengthening Denmark's surveillance of the airspace in connection with the upcoming EU summit in Copenhagen," the ministry said in a statement.
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In Denmark, the civilian-military Aalborg airport was shut two nights in a row last Wednesday and Thursday, with planes grounded.
Danish police said the drones followed a similar pattern to the ones that caused a shutdown at Copenhagen airport a few days earlier.
Police said drones had also been observed near airports in the Danish towns of Esbjerg, Sonderborg and Skrydstrup - where Denmark's fleet of F-16 and F-35 fighter jets is based.