Equality and inclusion organisation Kick It Out condemned the video as a "disgrace" and the Press Association understands the fans were turned away from the Europa League quarter-final in the Czech Republic after they were identified as members of the group in question.

A statement on Chelsea's website read: "Chelsea FC finds all forms of discriminatory behaviour abhorrent and where there is clear evidence of Chelsea season ticket holders or members involved in such behaviour, we will take the strongest possible action against them.

"Such individuals are an embarrassment to the vast majority of Chelsea supporters who won't tolerate them in their club."

Liverpool also released a statement, thanking Chelsea for their urgent action on the matter and confirming that they are working with Merseyside Police "to ascertain the facts around this footage with the aim of identifying individuals featuring in it."

Four Chelsea supporters were suspended by the club for abusing Raheem Sterling during Manchester City's 2-0 Premier League win at Stamford Bridge on December 8.

Then Chelsea condemned anti-Semitic chanting by Blues fans during the club's 2-2 Europa League draw at MOL Vidi on December 13.

A Chelsea statement at the time branded that chanting "abhorrent", saying it "shamed the club". The Blues avoided punishment however, after UEFA ended disciplinary proceedings over the incident in February.

Chelsea continue to run the high-profile Say No to Anti-Semitism campaign.

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