UEFA has opened disciplinary proceedings against Nice and Koln after crowd trouble marred a Europa Conference League match between the teams.
Thursday's group game on the French Riviera saw a delayed kick-off due to fans clashing in the stands and missiles being thrown.
Reports also cited trouble around the city prior to the match, with vandalism and damage to the French team's official club shop.
A number of fans were injured, and European football's governing body confirmed the start of disciplinary proceedings.
In a statement, UEFA said: "Disciplinary proceedings have been instigated in accordance with article 55 of the UEFA disciplinary regulations following the UEFA Europa Conference League group stage match between OGC Nice and 1. FC Koln (1-1) played on 8 September 2022 in France."
Both clubs have been charged regarding the 'throwing of objects', 'lighting of fireworks' and 'crowd disturbances', with Nice also facing five further charges relating to their hosting of the game.
Nice president Jean-Pierre Rivere said on Friday: "We've had enough of this. When you experience it live, it's terrible. When the next day you experience it a second time with hindsight, it's even worse because we have terrible images. It can't go on.
"I'm not in the habit of leaving a ship when things are rocking. But when you see that, you inevitably say to yourself: 'What am I doing here?'."
A number of Paris Saint-Germain supporters were identified as being among those involved in fighting.
French sports minister Amelie Oudea-Castera expressed a fear for the safety of the ordinary supporter, looking to avoid trouble at all costs but still coming face to face with hooliganism.
She said, quoted by RMC: "We are fed up, we are really fed up that our sport is soiled in this way, that we can no longer tell ourselves that we are going with our kids in a serene and safe way to a stadium.
"I have a knot in my stomach because it's starting again, Nice-Koln, with incredible violence, shocking images on social networks. We really have to find the solutions together to get through this, to ensure that this violence which is penetrating more and more into our society stops at least at the door of our stadiums."
Koln said they would work closely with police to identify perpetrators.
Managing director Christian Keller said: "We are all very upset about what happened. That has nothing to do with football and counteracts the values of FC Koln.
"With both clubs, it was a small minority of less than 100 people each that caused the excess violence in the stadium. Over 7,900 of the 8,000 spectators in the Koln block have nothing to do with the incidents. A blanket condemnation of our fans and in particular the active fan scene is therefore wrong."