Security and safety at German football stadiums has again been brought into question after a group of hooligans forced a brief delay at a Bundesliga match over the weekend by setting off fireworks and flares.
Bayer Leverkusen's 3-1 win at home to Eintracht Frankfurt on Saturday was halted for six minutes in the first half after fireworks and flares set off by away fans started landing at one corner of the pitch.
Referee Wolfgang Stark walked the players off as thick smoke filled Leverkusen's Bayer Arena and the players' safety could no longer be guaranteed with fireworks exploding from the fan block filled by Frankfurt supporters.
The German Football Federation (DFB) have said they will investigate and both clubs expect to receive five-figure fines.
Stadium security is a hot debate here after the clubs in Germany's top two leagues voted in December to accept the German Football League's (DFL) controversial safety paper, sparking nationwide protests by fans.
Flares and fireworks ignited by fans in the league's stadiums are a key issue as, under the new measures, clubs can insist on full body searches of supporters -- something Leverkusen chose not to do on this occasion.
Leverkusen chairman Wolfgang Holzhaeuser has suggested Bayer will pay for any fine by raising prices for away fans in future by between three to five euros per ticket.
"We're presenting this as an idea," he said.
"Ultimately, there will probably be a five-figure sum which we will have to pay."
While some fans were frisked before the same match last season, Bayer waived the right to search supporters on this occasion.
"At that time there were hints (of trouble), but that was not the case this time," Holzhaeuser said with four perpetrators having already been identified.
Frankfurt chairman Heribert Bruchhagen was furious with the fans responsible.
"This involves a tiny minority who we have to get out of the stadiums," he said.
"Only excluding them will help. They want to provoke and use football as a platform, the have no interest in football."