On Sunday evening, five drones were reported flying over the Doel nuclear power plant, located near the port city of Antwerp.
"Initially, we detected three drones, but later confirmed five. They were airborne for about an hour," stated Engie spokesperson Hellen Smits to POLITICO.
She noted that the first reports of the three drones came in around 10 PM on Sunday, adding that they did not disrupt the plant's operations. The Belgian National Crisis Center, which is currently monitoring the situation, confirmed the incident.
Earlier that evening, air traffic at Liège Airport was halted following numerous drone sightings, with flights stopping around 7:30 PM and resuming in less than an hour.
Brussels and Liège airports had experienced disruptions last week as drones were also spotted over military bases and the port of Antwerp.
On Thursday, a National Security Council meeting took place in Belgium, after which Interior Minister Bernard Quatennens assured that authorities are "keeping the situation under control".
While the government has refrained from speculating on the origin of the drones, Belgian intelligence agencies suspect foreign involvement, with Moscow considered the most likely source. Defense Minister Theo Francken described Russia as "certainly the most obvious suspect".
On Sunday, the United Kingdom announced it would join France and Germany in sending personnel and equipment to assist Belgium in countering drone incursions around sensitive sites.