Three Chelsea fans were stopped from entering Slavia Prague's stadium for Thursday's Europa League game after an alleged racist chant about Liverpool's Egypt international Mohamed Salah circulated on social media.
Chelsea, who visit Premier League leaders Liverpool on Sunday, put a statement on their website https://www.chelseafc.com/en/news/2019/04/11/club-statement?cardIndex=0-0 condemning any form of discriminatory behaviour after a video showed supporters singing in an apparent derogatory reference to the Egyptian player.
Merseyside Police said they were investigating publication of offensive Tweets made in relation to a Liverpool player.
Ex-Chelsea forward Salah, Player of the Year in England last season and winner of the African Footballer of the Year award for the second time in a row in January, is of Muslim faith.
Chelsea said: "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."
Chelsea's Italian manager Maurizio Sarri was asked at the post-match press conference following his side's 1-0 quarter-final, first leg win over Slavia Prague if the Premier League club was right to stop the fans attending the match.
"I don't want to speak about something that I don't know. I did not see the details. Of course it is right that the club made a very strong decision," he told reporters.
Liverpool said in a statement https://www.liverpoolfc.com/news/announcements/345516-liverpool-fc-statement on their website: "The video circulating online, showing vile discriminatory chants being aimed at one of our players, is dangerous and disturbing.
"This behaviour needs to be called out for what it is - unadulterated bigotry."
Liverpool added that the club were working with Chelsea and Merseyside Police to identify the people in the video.
The police added: "The language used in the Tweets is abhorrent and we are taking the reports extremely seriously.
"...we understand a number of individuals who are currently in Prague for the Slavia Prague v Chelsea (Europa) League game have been identified and have had their match tickets rescinded for this evening's fixture."
The anti-discrimination organisation Kick It Out condemned the latest racist abuse aimed at a footballer.
"It’s not on the terraces, but it’s still a disgrace. We don’t want fans like that anywhere near our game," it tweeted.
"We will be liaising with @ChelseaFC to ensure those involved are identified and punished swiftly and effectively."
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