Chelsea have claimed that they will ban supporters for singing a racist song and preventing a black man from boarding the Paris Metro.
A video released by The Guardian shows a group of supporters preventing the man from getting onto the train before chanting "We're racist, we're racist and that's the way we like it" as people wait on the platform.
The footage emerged shortly after Chelsea played out a 1-1 draw with Paris Saint-Germain in the first leg of their Champions League last-16 tie on Tuesday evening.
A statement from the club read: "Such behaviour is abhorrent and has no place in football or society. We will support any criminal action against those involved, and should evidence point to involvement of Chelsea season-ticket holders or members the club will take the strongest possible action against them, including banning orders."
Reports earlier on Tuesday suggested that French police had used tear gas following an altercation involving Chelsea fans before the game.