BRUSSELS

Belgian security services suspect a state actor, most likely Russia, is behind recent drone incidents that disrupted air traffic and military operations, sources told the Belga news agency Wednesday.

The issue was discussed during a preparatory meeting of Belgium's National Security Council, which will officially convene Thursday with Prime Minister Bart De Wever and federal deputy prime ministers.

Officials said several factors indicate foreign involvement. The drones reportedly flew in formation, operated in complete darkness, and targeted sensitive military sites, including Kleine-Brogel, which hosts US nuclear weapons and is set to receive F-35 fighter jets.

Authorities said the operations are beyond the capabilities of hobbyist drone users.

Defense Minister Theo Francken described the incidents as "coordinated and deliberate," calling for swift action, including new detection and counter-drone systems.

Flights at Brussels Airport were suspended twice late Tuesday after three drones were observed in the area. The airport confirmed Wednesday morning that 40 flights had been canceled while several others faced delays.

Liege Airport also faced disruptions, while drones were reported near military bases in Kleine-Brogel, Schaffen, and Florennes.

The National Crisis Center has been activated to coordinate the response after drones were detected over Brussels Airport as well as the Kleine-Brogel and Florennes military air bases, both key installations of the Belgian Air Force.

Local police also confirmed drone sightings over the military bases, but said the aircraft could not be intercepted.

This is the first time air traffic at Brussels Airport has been halted due to drone activity, an issue that has become increasingly common across Europe. Similar incidents have recently disrupted operations at airports in Copenhagen, Oslo, Aalborg, and Munich.

European leaders have blamed a number of recent drone incidents on Russia, while Moscow has denied any involvement.