Lyon and Paris Saint-Germain supporters clashed on a highway leading to the venue of the French Cup final a few hours before kickoff on Saturday.

Supporters threw flares and windows were smashed on buses full of supporters.

The final was deemed a very high security risk by the national police division for the fight against hooliganism, which put the threat level at five on a scale of five, according to RMC Sport.

Lyon and PSG ultras have a long-standing rivalry and were expected to travel to Villeneuve d’Ascq for the final.

The French Cup final was relocated to Stade Pierre Mauroy in the north of France because of preparations in Paris for the Olympic Games.

Violence has stained French football all season.

A Nantes supporter was stabbed to death by a driver whose vehicle was carrying Nice supporters before a league game in December.

A league game between Montpellier and Clermont was abandoned in October after a Montpellier supporter threw onto the field a firecracker which exploded near Clermont goalkeeper Mory Diaw.

Also in October, a league game between Marseille and Lyon was postponed after then Lyon coach Fabio Grosso suffered a serious head injury when the team bus was hit by thrown objects on the way to Stade Velodrome, shattering some windows. Grosso's deep cut above his left eye required stitches and he wore a large bandage around his head. Inside the stadium, Lyon supporters were also seen making Nazi salutes and monkey gestures.

Ultras have been targeting buses carrying supporters and there have been more than a dozen attacks this season.