Belgium’s defence minister has voiced alarm following a series of unidentified drone flights over the weekend near a military base housing US nuclear weapons.
He has suggested that the incidents appear to be part of a "spying operation".
Theo Francken confirmed that drones had penetrated the airspace around the Kleine Brogel air base in northeast Belgium across two distinct phases on Saturday and Sunday nights.
He told public broadcaster RTBF that the initial phase involved "small drones to test the radio frequencies" of Belgian security services.
That was followed by "big drones to destabilise the area and people".
Mr Francken said: “It resembles a spy operation. By whom, I don’t know.”
He said he has “a few ideas” but is going to be “careful” about speculating in public.
It comes after similar drone sightings in October above another Belgian military base situated near the German border, where the operators also remained unidentified.
Russia has been blamed for a number of airspace violations, notably in Estonia and Poland, in recent months. But the perpetrators of a series of mysterious drone flights in Denmark and Germany have been harder to pin down.
A late evening drone sighting at Berlin’s Brandenburg airport on Friday suspended flights for nearly two hours. It was not clear who was responsible.
Mr Francken ruled out that the weekend drone flights in Belgium might have been a prank.
He said that the security services’ “jammer didn’t work because they tested our radio frequency, and they changed frequency. They have their own frequencies. An amateur doesn’t know how to do that.”
Asked why it was not possible to shoot the drones down, Mr Francken said: “When they’re over a military base we can shoot the drones down. When it’s nearby, we have to be very careful because they can fall on a house, a car, a person. That’s completely different.”
This can pose legal challenges too. “It’s not entirely clear. We have to clarify the legal grounds,” he said.
Mr Francken lamented that Belgium “is chasing after the threat” posed by such drone flights.
“We should have bought air defence systems five or 10 years ago” that can deal with drones, he said.
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