An airport employee spotted the drone carrying what authorities described as ‘an unknown explosive device’.

German authorities have launched an investigation after police removed the detonator from an explosive device attached to a drone found at Leipzig/Halle airport.

The airport’s north runway reopened on Wednesday after being closed for about two hours, while the south runway remained out of use due to scheduled maintenance.

Several flights, including a passenger aircraft, were diverted to other airports after a flying object was reported near the airport shortly before midnight. Police deployed an explosives-disposal robot to examine the object.

Authorities later said an airport employee discovered the drone near the runway carrying what they described as “an unknown explosive device”. Police examined it and removed its detonator, but did not provide further details about the nature of the device.

The probe is being led by prosecutors in the eastern state of Saxony who are responsible for politically motivated and “extremist” crimes, although authorities have not identified any suspects or attributed responsibility.

Meanwhile, an apparent second flying object collided with a freight aircraft after it aborted its landing because the runway was closed.

The aircraft diverted to Hannover airport, where officials found slight damage during an inspection. Authorities have not said whether the second object was connected to the drone found near the runway.

Authorities said there was no danger to travellers or airport employees, and flights were operating normally on Wednesday.

Photos from the scene showed police technicians working with an explosives-disposal robot near a Ukrainian Antonov cargo aircraft parked at the airport, although authorities have not indicated the aircraft was the intended target.