Tottenham Hotspur have released a further statement commenting on the claims that Antonio Rudiger was racially abused in their 2-0 defeat to Chelsea.
The Germany international reported to club captain Cesar Azpilicueta that he had heard or seen racial abuse coming from the home support at Tottenham Hotspur Stadium during the Blues' victory on Sunday.
In a club statement posted to their official website, Spurs revealed they had employed lip readers and local authorities to help identify the culprits, with the Tottenham hierarchy contacting representatives from the Blues for more information.
Spurs also confirmed they would hand a lifetime ban to any fan found guilty of racially abusing Rudiger, or any other players. However, they admitted that their findings are as of yet inconclusive.
Meanwhile, Tottenham boss Jose Mourinho has urged fans to challenge racist abuse if they hear it in the stands.
While Spurs' findings for perpetrators among the home support have yielded nothing yet, the Guardian report that police have arrested a Chelsea supporter on suspicion of abusing Son Heung-min during the encounter.
Addressing the events that marred the weekend's London derby, Mourinho stated (as quoted by the Times): "My message is that it is not fair to say Tottenham fans. One Tottenham fan is not [representative of all] Tottenham fans.
"If I have to say something, it is to ask my supporters, the Tottenham supporters, to keep doing exactly the same that they are doing with the team, which is supporting the team in a season that has not been easy at all - since the beginning of the season it has been difficult.
"To ask them to be exactly the same and, obviously, to look to the guy to the left and look to the guy to the right, and listen to the guy behind and listen to the guy in front.
"And if anyone has any little manifestation, to try between them to kill [racism] immediately. That’s the only thing I can ask for."
The Spurs manager went on to give his opinion on why instances of racism continually crop up English football
Mourinho explained: "I think society needs help. Then football is a micro society if you can call it. Do we need help? Yes, but society needs help.
"We need to eradicate any form of discrimination. In this case, we are speaking about racism, and yes, football needs help, but society needs help.
"It is happening before, and what I fear is that it is going to happen again in the future. That’s the problem. What I see is an evolution in the protocol. And I think that’s fine.
"I think in this moment, any person - including the players - they have, according to the protocol, the freedom to stop. They have the freedom to go to the referee, the freedom to go to their managers. This is one step. Any decision that can be made by superior authorities I will support."
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