Travellers were left stranded for hours at Eindhoven Airport on Saturday, after flights were suspended following sightings of drones. The incident is just the latest in a series of airspace intrusions by unidentified UAVs, that have caused travel chaos in Europe.

Drones were first spotted flying over the nearby Volkel air force base late on Friday. Dutch military personnel tried to shoot down the drones, but the UAVS were able to fly away without being damaged. Volkel Air Base is used by the Royal Netherlands Air Force and also hosts a US Air Force squadron as part of NATO.

The drones reappeared on Saturday, forcing a closure to airspace above the city and to the suspension of passenger flights.

Eindhoven Airport curtailed operations from between 19.00 and 23.00, with nine flights diverted to other cities.

Commenting on the incident, the Dutch Defence Minister Ruben Brekelmans said: "The Ministry of Defence has taken measures, but due to security reasons, it cannot yet share more information about the manner in which this was done. Disruption of air traffic with drones is unacceptable. So we took action against it.”

A number of military bases have been targeted by drones in recent weeks in northern parts of Europe,

UAVS were spotted at other Dutch air bases, as well as at facilities in neighbouring Belgium, Denmark and Germany.

Investigators have been unable to identify the origins of the drones, but the finger of suspicion has been pointed at Russia.

Officials believe the drones are part of the Kremlin's "hybrid warfare", as countries supporting Ukraine have been targeted.

However, the Kremlin has denied any involvement in the incidents, brushing of the accusations with disdain.

European Defence Minister form 10 countries have agreed to create a "drone wall" to prevent further intrusions.

At the same time, individual nations have sought to secure their own anti-drone defence measures.