Lancashire Constabulary are investigating after Burnley and Cardiff supporters clashed outside Turf Moor on Saturday.
A video circulated on social media appears to show a group of fans fighting after the game, with one man apparently knocked unconscious after hitting his head on a wall.
A police spokesman told Press Association Sport they were aware of the incident but no serious injuries had been reported to them.
The police are also looking into offensive social media posts made after the Clarets’ 2-0 win over their relegation rivals.
“Burnley FC is aware of a post-match incident involving two sets of supporters outside Turf Moor after Saturday’s game with Cardiff City,” said a statement from Burnley.
“In addition, a number of offensive posts have been reported to the club, and we are working with Lancashire Constabulary on both these issues.”
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