Fans, police clash before Bayern Munich vs. Olympiakos match

Bayern Munich supporters and Greek police officers got into an ugly altercation inside Karaiskakis Stadium in Piraeus, Greece before the start of the Champions League match between Bayen Munich and Olympiakos.

Bayern Munich supporters and Greek police officers got into an altercation inside Karaiskakis Stadium in Piraeus, Greece before the start of Wednesday's Champions League match between Bayern and Olympiakos FC. 

It is unclear what provoked the incident. 

Bayern Munich ended up winning the match 3-0 behind two goals from Thomas Muller and another from Mario Gotze, vaulting the German club to the top of Group F after one match. 

Bayern was a Champions League semifinalist last season, ultimately bowing out to Barcelona. 

Schreckliche Prügelszenen im Gästeblock in Piräus #OLYFCB #fcbayern #ChampionsLeague pic.twitter.com/Mj66xwqldB

— Michael Humpa (@micmuc) September 16, 2015

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