LONDON (AP) -- Police say a man has been arrested for making an alleged racist gesture during a League Cup match between Chelsea and Manchester United.

A spectator sat in the Chelsea supporters' end was pictured making a monkey gesture during the home side's 5-4 extra-time victory over United last Wednesday in the round of 16.

The Metropolitan Police says Monday that a 28-year-old man "was arrested on suspicion of a racially aggravated ... offense and currently remains in custody.''

The London police force are also investigating allegations referee Mark Clattenburg directed a racial insult at Chelsea midfielder John Obi Mikel during a Premier League match between the two clubs four days earlier.

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