West Ham United joint-chairmen David Sullivan and David Gold have called on all of the club's supporters to report any abuse heard during this weekend's match against Chelsea.
The Hammers have come under the spotlight after a host of the Premier League outfit's fans could be heard singing anti-Semitic chants during West Ham's 3-1 defeat to Tottenham Hotspur last weekend.
In an open letter on the club's official website Sullivan and Gold said: "We have said to them what we will say to you now - it is up to us all to not tolerate anything that we deem to be unacceptable when supporting West Ham United. In the rare case that you do see or hear anything inappropriate, there are a number of ways you can report the matter.
"Two of the easiest ways are to speak to your nearest steward at the stadium or use the Boleyn Ground's anonymous fan phone number - 07860 404 069 - where all calls will be treated in the strictest of confidence.
"We have made it very clear over the past week that we will not tolerate any form of discriminatory behaviour and one by one we will root out those fans that do not deserve to represent this great club of ours."
The former Championship side have already issued a lifetime ban to a supporter.
