UEFA have formally opened an investigation into a number of violent incidents that broke out during Dynamo Kiev’s round of 32 second leg against French side Guingamp on Thursday.
With the score at 2-0 to Kiev and a place in the next round in sight, a group of Kiev supporters burst their way past stewards in order to attack the small group of traveling Guingamp fans.
The game was halted for around 15 minutes in order to quell the violence, with the Guingamp supporters evacuated from the ground for their own safety.
With no visiting supporters to fight with the Kiev fans then decided to fight amongst themselves.
Dynamo Kiev goalkeeper Oleksandr Shovkovskiy even went into the crowd to try and calm them down but only ended up trying to separate fighting supporters alongside security guards.
The match was eventually restarted with Kiev scoring a third goal to complete a 4-3 aggregate victory
The Guingamp president, Bernard Desplat, was horrified at the violent scenes and told the French media:
"I saw a stadium at war with rabid dogs that wanted to fight.
"There were 11 heroes in Guingamp colours on the field because organising a match in these security conditions, when the safety of a certain group is not assured, is catastrophic for football.
"These are not fans, they are militiamen. Restarting play? How do you expect the players to focus on their game? It was extremely dangerous. This match could only have happened in Ukraine under these conditions."
UEFA have since formally opened disciplinary proceedings against Kiev with a hearing set for March 4.
Punishments range from a fine, ordering their home tie against Everton to be played at a neutral venue or behind closed doors. Kiev could even be thrown out of the competition though that appears unlikely.
Whatever happens it is likely to complicate still further what is already a difficult away trip for supporters and players alike.