Brussels Zaventem Airport was temporarily closed on Tuesday night after a report of a drone in its airspace.

The drone sighting, which occurred shortly before 8 p.m., prompted the suspension of all incoming and departing flights, a spokesperson for skeyes, Belgium’s air traffic controller, told local media.

“For safety reasons, all air traffic has been shut down for the time being,” the spokesperson said. All incoming flights were diverted to Liège.

The incident is the latest in a series of drone sightings across Europe that have sparked security concerns and disrupted air travel. On Friday, Berlin-Brandenburg Airport also diverted flights following a drone alert.

While this is the first reported drone sighting over Brussels Airport, suspicious unmanned aircraft were spotted earlier this month over several Belgian military bases. Defense Minister Theo Francken said those drones were believed to be attempting to spy on fighter jets and ammunition depots.

An investigation is underway into the incursions over the Kleine Brogel air base in northern Belgium.