Manchester City have apologised to Manchester United defender Rio Ferdinand after he was struck by a coin during their meeting at the Etihad Stadium.
The 34-year-old was hit with a flying object by a City fan while he was celebrating Robin van Persie's winning goal for United, which gave them a 3-2 victory.
The Premier League champions insist that they will work with the police to investigate any instances of bad behaviour from their fans.
A statement on the club's website read: "Manchester City FC security officials are co-operating fully with Greater Manchester Police in relation to events leading up to the throwing of missiles onto the field of play, and between the two sets of supporters, during today's game against Manchester United.
"Manchester City wishes to offer its sincere apologies to Rio Ferdinand. The club unreservedly condemns the actions which led to his being injured.
"GMP's review of all fan behaviour at today's match will be fully supported by the club, through the provision of CCTV footage and eyewitness accounts. Following this review, and any associated police action, the club will also apply its own disciplinary policies for any fans found guilty of offences."
United are now six points clear of City in the Premier League following their victory in the Manchester derby.
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