Chelsea have suspended four people from attending matches while an investigation into the alleged racial abuse of Manchester City forward Raheem Sterling takes place.
The incident involving the 24-year-old occurred during City’s 2-0 loss at Stamford Bridge on 8 December.
Chelsea are “fully supporting” an ongoing police investigation.
A club statement said evidence of racist behaviour will result in “severe sanctions, including bans”.
“Chelsea Football Club finds all forms of discriminatory behaviour abhorrent,” the statement continued, adding that the club “will also fully support any criminal prosecutions”.
Manchester City welcomed Chelsea’s decision to issue suspensions.
A club statement said: “The club and Raheem are fully engaged with Chelsea FC and the investigating authorities as they continue to examine the events in question.
“Manchester City and Raheem are committed to working with all relevant parties and organisations to support the objective of eradicating racism from the game.”
Social media users posted a video of an incident during which Sterling was shouted at as he collected the ball from behind the goal.
Sterling said he “had to laugh” when he heard the remarks because he expects “no better”.
A subsequent Instagram post from the England international saw him question the way the media portrays black players and has prompted debate between stakeholders in the game.
The Professional Footballers’ Association has said negative press coverage of Sterling “emboldens racist rhetoric”, adding the former Liverpool player is “often singled out”.
Meanwhile, Liverpool manager Jurgen Klopp says Sterling’s reaction to an incident of alleged racist abuse at Chelsea was “just brilliant”.
Klopp praised Sterling for keeping his composure during the incident, which is being investigated by both Chelsea and the Metropolitan Police.
“I watched the game obviously and I saw the situation when Raheem went for the corner with a few guys shouting at him,” Klopp said.
He continued saying, “His reaction was just brilliant. You saw his face and he gave the right response, not to react for these people. They do not earn any reaction. They do not deserve any respect.
“I am obviously not surprised that things like this still happen. They do not stop only because we talk now about it.
“There needs to be punishments for that. That is how it is because as long as people are silly enough to do things like this they need to get punished for it.
“What I like is that I think 95 per cent or even more of the people are not like this so we should try to find the right amount of attention for these people.
“Punish them but don’t talk too much about them because they do not deserve that we talk about them.”