Around 200 people were arrested Saturday as ugly scenes marred the 141st Revier derby between Borussia Dortmund and Schalke.
Despite repeated appeals by both clubs for their fans to behave during the week, violent skirmishes were reported in the build-up to a game which Schalke won 2-1 in Dortmund.
According to local police reports, a restaurant was gutted by Dortmund followers "with furniture ripped apart and used as missiles against opposition fans and police."
One police car was damaged as mounted police, riot police and agents with dogs were brought in to keep the spectators apart.
Hours before the game kicked off at 3:30 p.m. local time, followers of both clubs attacked police who tried to segregate them in the Westphalian city and water cannons and tear gas had to be deployed to keep them at a safe distance.
Mounted police were "attacked by Dortmund hooligans with cobble stones," according to a police report.
The first reports of trouble were circulated almost three hours before kick-off when "a group of around 100 masked Schalke fans left the underground station and went on the rampage, lighting flares on their way towards the stadium".
"This has nothing to do with football supporters and we don't want to see them in Dortmund," said the Dortmund police chief director Dieter Keil.
There was further trouble inside the Westfalenstadion with Schalke fans lighting flares and displaying offensive banners, despite bans on such material.
The culprits were all caught on video, however, and will be prosecuted, according to the police statement.
The majority of those arrested were Schalke followers, with the police suspecting the clashes had been organized by the rival groups.
Disturbances were kept to a minimum after the game with the police successfully able to keep both sets of fans apart.