Belgian Defense Minister Theo Francken said that the case of drones, which caused the cancellation of dozens of flights at Brussels airport, was not the work of amateurs, DPA reported, BTA reported.
"It is clear that this is about something bigger", Francken told the defense committee of the House of Representatives of the Belgian parliament, quoted by the Belga agency. "We need to react quickly," he added.
At least 54 flights were cancelled at Brussels airport in the early hours of today after it was grounded last night due to drone sightings.
Unmanned flying objects were also spotted over a military base in Wallonia and another used by NATO at Kleine Brogel in Flanders.
Franken referred to a "hybrid threat" that was "real and serious," noting that the incident was similar to others that have occurred recently across Europe.
"The drone incidents are coordinated in time and space, they are deliberately aimed at disrupting air traffic," he said, adding: "Classic radio frequencies are not used, but mobile networks of the fourth and fifth generation".
"These are (semi)professional drones that fly in formation – something that not everyone can achieve. Various indications point to a structured operation", Franken pointed out.
To counter this threat, an air surveillance center must become operational, Franken also said. He also said he wanted to propose the rapid purchase of drone detection and protection systems.
Six drones were spotted over the Kleine Brogel military airport, Belga reported, citing the city's mayor, Steven Mattei.
According to unconfirmed reports, the base is one of the places in Europe where US nuclear weapons are stored.
Drones were spotted several times over the Kleine Brogel base over the weekend.
Overflights of unmanned aircraft forced the airport in the Belgian capital to suspend operations twice last night, Belga reported.
Yesterday's incidents led to the cancellation of 41 flights. Between 400 and 500 people had to spend the night at the airport, public broadcaster RTBF reported.
The Belgian government is expected to hold an emergency meeting over the repeated drone overflights.