"As well as the referee and the assessor reporting the incident to us, Greater Manchester Police made it clear, to ourselves and the club, that they believed the the behaviour to be inappropriate and contributed to the disorder that followed the match, " said an FA spokesman.

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"We absolutely condemn all of the disorder that has occurred at Upton Park, " said an FA spokesperson.

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"We are seen as one of the leaders, if not the leader, in the way that we have tackled hooliganism and disorder in our grounds over the past 30 years, " Adrian Bevington, the FA's director of communications, told BBC Radio 5 live.

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