A battle between football fans and police broke out in Lausanne on Saturday during a local derby.
Geneva Servette was playing Lausanne Sport.
Police say the trouble makers came from both sides.
Supporters threw fireworks at the police which responded with water cannon, rubber bullets and pepper spray.
The trouble started even before the match. Some Geneva supporters lit fireworks and sprayed graffiti while walking from the train station to the stadium.
Authorities from both cantons are now discussing possible sanctions against the clubs. That could mean games being played behind closed doors or banning opposing supporters.
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