Drones flying over airports, commercial sites and other sensitive infrastructure in Europe is a growing phenomenon which EU leaders blame on Russia, and preventing the disruption they cause will prove a tough technical challenge, observers say.
Detecting the drones, making them non-operational by jamming them, or even shooting them down, are all complex and hazardous tasks. And while Russian involvement is suspected, it is difficult to prove.
Concerns are growing that such disruptions could be part of Russian hybrid war tactics three-and-a-half years into its invasion of Ukraine, as most European countries double down on their support for Kyiv including by delivering military hardware.
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