Air traffic above the southern Dutch city of Eindhoven has been suspended after unidentified drones were spotted near the airport.
Drones were first observed late on Friday over the nearby Volkel air force base. Weapons were deployed to try to shoot them down but the devices got away.
Following more drone sightings near the main airport on Saturday, the airspace in the area was closed to both civilian and military flights. Dutch Defence Minister Ruben Brekelmans said "counter-drone assets" were ready to intervene.
It is the latest in a series of such incidents at military installations and airfields in northern Europe in recent months. Russia has denied accusations it was involved in them.
As well as being used by the Royal Netherlands Air Force, Volkel Air Base hosts a US Air Force squadron as part of Nato.
