A video taken from the 2-1 loss at the Etihad Stadium appeared to show a man making a racially abusive gesture during the second half when United players Fred and Jesse Lingard were making their way towards the corner where City fans were located.
The club have contacted Greater Manchester Police and issued an immediate statement after the match to confirm they are investigating the matter, adding that “the club operates a zero tolerance policy regarding discrimination of any kind” and promised that life-time bans will be issued to anyone found guilty.
City also confirmed that police are looking into supporters who appeared to throw objects at Fred during the same incident.
A Manchester City club statement read: “Manchester City FC are aware of a video circulating on social media which appears to show a supporter making racial gestures during the second half of the match against Manchester United this evening.
“Officials from the club are working with Greater Manchester Police in order to help them identify any individuals concerned and assist with their enquiries.
“The club are also working with GMP regarding an instance of objects being thrown onto the field of play.
“The club operates a zero tolerance policy regarding discrimination of any kind, and anyone found guilty of racial abuse will be banned from the club for life.”
More than one United player reported the alleged racial abuse to the referee, and manager Ole Gunnar Solskjaer echoed City’s promise to ban any guilty individuals for life.
"I've seen it on the video,” Solskjaer told Sky Sports. “Fred and Jesse [Lingard] in the corner taking coins from the City fans first of all, so they've got to go away.
"And then there's this not-so-intelligent fella chanting racist abuse towards my two players and I hope City and the authorities will deal with it, because he shouldn't be watching football again. Not live, anyway.
"We have to stamp it out. We keep talking about it every single week and it's not acceptable. He should not be allowed back into a ground. That's how simple it is."
United forward Marcus Rashford added: "I wasn't aware of it during the game but it can happen and we've seen it happen lately. The fact it is still happening is not good enough."
Anti-racism campaign Kick It Out said they were “inundated” with complaints regarding the alleged incident and will contact both clubs in order to address the case.
“We have been inundated with reports of alleged racist abuse from a number of individuals during this evenings Manchester Derby. We will be contacting both clubs to offer our support and hope swift action is taken to identify the offenders.
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