Sixty five people were arrested after trouble flared in Paris on Thursday night between football supporters ahead of the final of the Coup de France.
Six people were injured, with one in a serious condition, the Paris police confirmed on Friday.
Fans of Nice and Lens had gathered in the capital ahead of the final, which will be played at Stade de France on Friday night, and on Thursday evening around 100 Nice fans gathered in the 10th arondissement "clearly looking for trouble", according to the police chief.
The fans became involved in a mass brawl at the Quai de Valmy on the Canal Saint-Martin. Police intervened and 65 people were arrested for "involvement in a group with the intent to commit violence".
Some of the fans were found to be carrying knives, balaclavas and protective gloves.
