In an open letter to the fans of FC Schalke 04 and Borussia Dortmund, the police have urged peaceful behaviour at the Revier derby.

“The federal police will consistently intervene against persons who arrive to act out their aggression and commit violent offences,” the letter published on Friday reads. “Our main concern is to ensure a safe arrival and departure for peaceful football fans and other travellers.”

Clashes between rival fans are feared around the match between the two Ruhr clubs. Among other things, police pointed out that no “dangerous” items including glass bottles and drink cans were allowed to be carried around Gelsenkirchen’s main railway station ahead of this Saturday’s Bundesliga encounter (6.30pm/DAZN). Additional trains will be used to bring BVB fans to and from the match.

The letter concludes with an appeal: “Help to make the derby a sporting and fair event and, despite all the rivalry and emotionality, treat each other with respect!”