A video showing a group, believed to be Chelsea fans, singing a racist song has been condemned by equality and inclusion organisation Kick It Out.
The video, which has been widely shared on social media, showed the group singing "Salah is a bomber" apparently in reference to Liverpool forward Mohamed Salah.
"It's not on the terraces, but it's still a disgrace. We don't want fans like that anywhere near our game," Kick It Out tweeted.
"We will be liaising with @ChelseaFC to ensure those involved are identified and punished swiftly and effectively. #KickItOut"
Chelsea declined to comment on the basis that it has not been established that these are Chelsea fans, but it is understood the club would prevent anyone they identified from entering their Europa League clash against Slavia Prague.
The Blues' first-leg quarter-final Europa League tie against Slavia takes place in the Czech Republic on Thursday night.
The Czech police have yet to respond to the Press Association's request for comment.
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