Chelsea have told supporters they'll take the "strongest possible action" against anyone who aims anti-Semitic abuse at Tottenham fans in Sunday's League Cup final.
The club has issued a statement on its website asking them to keep their support "positive" at Wembley.
Chelsea admit games between the clubs have "historically brought a deeply unpleasant and unwanted level" of anti-Semitic abuse from what they call a "small minority".
"After consultation between the Metropolitan Police and both clubs, we would like to remind supporters of their responsibilities on the day," read a statement on Chelsea's website.
"For a small minority, this game has historically brought a deeply unpleasant and unwanted level of anti-Semitic abuse, which has no place in football or anywhere in society. As such, we urge everyone to keep their support positive."
We're working with @ChelseaFC to find 7 men we want to speak to following reports of racist chanting. Can you help? pic.twitter.com/BtcVDPtfBk
— BTP (@BTP_UK) February 25, 2015
"Recent events in Paris have seen Chelsea fans united in their contempt for a mindless few," continued the statement.
"Chelsea is proud of the diversity within our club and our vision embraces equality regardless of race, gender, sexuality, disability or religion.
"We all share the common cause of supporting our team."
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