West Ham United will investigate claims that some of their fans were involved in racist chanting before Sunday's defeat to Tottenham.
It has been reported that supporters sang racist songs prior to the 4-3 loss against their London rivals.
According to the Daily Mail, the Football Association has passed footage of the alleged incident to police.
The club said in a statement to the paper: "We are a leading campaigner in the Kick Racism out of Football campaign and we will not tolerate racist behaviour. We will investigate this matter fully."
An FA spokesman added: "Racist behaviour has no place in football. We would hope that, if these individuals are identified, they will be issued with banning orders."