Belgium suspended air traffic at Brussels Airport on Nov. 4 due to a reported drone sighting in the area, according to the Belga News Agency.
The closure follows a string of suspicious drone incidents in Belgium and comes a day after the Belgian military gave orders to shoot down unknown drones spotted near the country's military bases.
A drone was seen near Brussels Airport the evening of Nov. 4, following sightings of several drones near Belgium's Kleine Brogel Air Base an hour before, the Belga News Agency reported. The airport suspended flights in response.
"For safety reasons, all air traffic has been halted for the time being," said Kurt Verwilligen, a spokesperson for Skeyes, Belgium's air traffic control agency.
It is the first time Brussels Airport has closed due to drone activity.
The Kleine Brogel Air Base, which houses Belgium's F-16 fighter jets and is widely believed to host U.S. nuclear weapons, has been plagued by suspicious drone activity over the past several days. Unknown drones were spotted over the airfield for three consecutive nights between Oct. 31 and Nov. 2.
Six more drones were reportedly spotted over the base the evening of Nov. 4.
Belgian Defense Minister Theo Francken said the incidents appear to be part of an espionage operation. He did not name a culprit but linked the drone activity to recent Russian airspace violations in Europe.
"The Russians are trying to do this in all European countries," Francken said. "Is it the Russians now? I can't say that, but the motives are clear and the ways of doing things like this are also very clear."
Mysterious drone sightings in Europe earlier this fall caused air traffic closures at airports in Copenhagen, Aalborg, Oslo, and Munich. The incidents followed a string of Russian airspace violations in NATO territory.
Brussels is home to NATO headquarters, making it the de facto capital of the alliance.
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