Police in the southern state of Bavaria said they, together with prosecutors, were looking into several incidents in which drones have flown over military installations in Manching and Neuburg an der Donau.

On Sunday police spotted up to 10 unmanned aerial vehicles flying in a secured military zone in Manching, which hosts a military aerodrome and is where the Eurofighter jet is developed by Airbus.

Eyewitnesses also saw several drones at the same site on December 16 and 18, as well as in the early hours of Christmas Day.

On December 19 three drones were spotted over at Neuburg an der Donau, also over a military air base.

The two sites lie around 20 kilometres (12 miles) apart just south of the city of Ingolstadt.

Police said they undertook "extensive investigations" into the incidents, including the deployment of helicopters, "as it cannot be ruled out that military installations and defence companies are being spied on in the context of Russia's war of aggression against Ukraine".

However, police have not yet been able to determine who was piloting the drones.

- 'Suspicious people' -

Police appealed to the public to forward any relevant information, including sightings of any "suspicious people or vehicles" near the two sites.

The incidents are being investigated for possible breaches of legislation prohibiting "taking images which threaten security".

In May 2024 a Eurofighter jet was damaged after colliding with a drone while landing at the site in Manching.

In recent months several drones have also been spotted at an industrial zone near the North Sea and near the US airbase in Ramstein.

Germany has been unsettled in recent years by a number of high-profile cases of alleged spying for foreign powers.

A Chinese woman was arrested in October in Germany accused of spying on defence industry installations.

Police also launched a probe in December against a Chinese man who was reported to have taken photographs at a naval base on Germany's Baltic Sea coast.

Late last year a series of mysterious drone sightings in the US state of New Jersey sparked worldwide curiosity, leading authorities there to announce drone flight restrictions.

However federal US officials insisted there was no "national security or public safety risk" linked to the sightings and rejected any suggestion of foreign involvement.

bur-jsk/fz/sbk

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