Werder Bremen general manager Frank Baumann has admitted the club flew a drone over Hoffenheim's training ground on Tuesday ahead of the two clubs' 1-1 Bundesliga draw.
Hoffenheim spotted an object flying over their training base during their final session prior to Wednesday's clash and alerted it to the police.
The flying of drones over groups of people in Germany is prohibited, and it had been alleged that the drone was being used by a Werder scout.
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Baumann did acknowledge Werder had someone in the area, though he insisted "anything that is illegal is unacceptable".