NATO has stepped up air defenses after a surge in mysterious drone sightings over military bases and airports across Europe, with incidents reported in Denmark, Spain, Norway, France, and Germany.

Denmark’s largest air base and Copenhagen Airport were repeatedly targeted, prompting a nationwide civilian drone ban during an upcoming EU summit.

Authorities suspect Russian involvement, with ships from Moscow’s “shadow fleet” linked to some incursions.

NATO has deployed surveillance platforms and a German frigate in the Baltic Sea, while Denmark installed advanced radar at its main airport.

Germany is considering new laws to authorize the military to shoot down drones, the U.S. Sun has reported.

Leaders across Europe describe the incidents as possible Russian “hybrid attacks,” and NATO allies are working on a large-scale “drone wall” defense system to counter ongoing threats.