Europe's top football body has warned it may ban England's and Russia's national teams from the Euro 2016 tournament if fan violence continues.
UEFA has launched disciplinary action against the Russian Federation in response to the latest in a number of incidents that have left dozens of people hurt.
UEFA, the Union of European Football Associations, is expected to hand down sanctions within days.
It is investigating serious crowd disturbances following Saturday's1-1 draw between Russia and England at the Euro 2016 tournament in France.
The trouble broke out inside Marseilles' Stade Velodrome, reportedly following an earlier confrontation between supporters of the two sides.
And it comes on top of days of street clashes involving English, French and Russian fans and riot police, in which more than 30 people were injured.
Europe's football governing body says it is disgusted by the recent events.
It has threatened Russia and England with expulsion from the tournament if their fans are involved in any more violence.
UEFA says it is also looking into allegations of racist behaviour and fans throwing missiles and fireworks.
France's interior minister, Bernard Cazeneuve, has endorsed UEFA's position.
"It is absolutely necessary that the national federations of countries whose supporters create incidents of this nature be punished for what happened -- inside the stadium, of course, at a minimum -- but also outside stadiums."
The Interior Minister says anyone arrested for violence could also be banned from competition stadiums and popular public areas in the nine host cities.
And he has requested police take measures on the sale, consumption and transportation of alcohol around matches.
The Russian team's head coach, Leonid Slutsky, says fan violence hurts the sport's reputation.
"Honestly speaking, I'm not aware of the situation. We were completely focused on preparing for the game, and I don't even know what is going on. But, in any case, that's not good to go hand in hand with football."
Russia's sports minister, Vitaly Mutko, initially downplayed the events at Stade Velodrome, but he says UEFA is right to investigate.
The English Football Association has highlighted what it regards as inadequate segregation measures between English and Russian fans.
Chief executive Martin Glenn also addressed UEFA's disciplinary action against the Russian Federation.
"As to what sanctions UEFA has formally charged the Russian Football Association for the disorder in the ground, both for the crowd violence, also the setting off of flares and other things, we'll let UEFA deal with that, but they clearly are holding Russia to blame for that."
Mr Glenn says the violence at Euro 2016 is the worst he has seen at a football event in decades.
"There's antisocial behaviour where fans are going out there to soak up the atmosphere if they're not going to the ground, but it's causing trouble for a stretched French police that have got other things to worry about."
There have been brief bursts of violence in Nice between Northern Irish and local fans.
And a few smaller incidents were linked to a match between Croatia and Turkey in Paris.
Overall, 90,000 police, soldiers and private security staff are deployed to maintain order during the tournament.
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