In a statement issued by the Barclays Premier League club on Friday morning, it is claimed supporters were subjected to "a number of assaults and unprovoked baton charges before, during, and after the game" at Vicente Calderon, which ended in a goalless draw that sent the Trotters through to the last 16.
The alleged behaviour of the police has prompted the club to take action, and they will liaise with Greater Manchester Police and the British Embassy in a bid to establish the precise course of events.
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