Bayern München CEO Karl-Heinz Rummenigge has criticised a section of the club's fans who were involved in an "extremely violent" attack ahead of Saturday's fixture against Schalke.
Violence broke out before the match in Gelsenkirchen, with unrest seemingly caused when the supporters' entrance into the stadium was delayed because of body searches at the gates in the aftermath of last week's terror attack at the Stade de France in Paris.
A Police statement described the attack as "extremely violent", and added that "only a swift and consequent intervention by police forces prevented worse. Several dozen from this violent group of people are being held."
Rummenigge has condemned the behaviour of those involved and said the club distanced itself "in every form from these so-called supporters of our club."
"Violence cannot and should never be tolerated," he said in a statement.
"I expected fans of FC Bayern to behave appropriately and sensitively. Almost all have done that, but unfortunately not all, and I am very disappointed."
The Bayern boss apologised to Schalke for the incident and praised the local police who "responded well considering the difficult situation of escalating violence."
The Bavarians won the match 3-1 thanks to goals from David Alaba, Javi Martinez and Thomas Muller, with Bayern now opening up an eight-point lead at the top of the Bundesliga standings.