Manchester City have condemed the behaviour of "a small number of individuals" after some of their fans were filmed singing offensive chants against Manchester United and England legend Sir Bobby Charlton.
The Premier League champions released a statement on Sunday after a group of their fans were caught on camera celebrating Charlton's death during their Premier League clash against Brighton at the Etihad on Saturday.
"Manchester City FC are extremely disappointed to have learned of reports of offensive chanting from a small number of individuals about Sir Bobby Charlton in some of the concourses of Etihad Stadium during half-time of yesterday's Premier League fixture against Brighton and Hove Albion," the club said in a statement.
"The club condemns these chants in the strongest terms and apologises unreservedly to the family and friends of Sir Bobby, and to all those at Manchester United."
Charlton's death was announced by United on Saturday. Meanwhile, City paid tribute to their former hero Francis Lee ahead of the game against Brighton.
"On this day of all days, when the stadium stood to pay tribute to our own legend in Francis Lee, Manchester City supporters should understand and appreciate as keenly as anyone the need for respect in our game," the club added.
"Our security team are studying CCTV footage of the concourse areas. We are thankful to those who have already come forward to report this matter.
"We continue to appeal for any information that can help us identify the individuals involved so that we can take the appropriate action to issue banning orders."
United will pay tribute to Charlton ahead of next Sunday's Manchester derby against City at Old Trafford in the Premier League.
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