A man has been arrested and interviewed by police after trouble at the end of a football match.
The crowd came on to the pitch after Forest won the Championship play-off match.
There are allegations that a Forest fan was stamped on by a Blades player.
A man was arrested on suspicion of assault after presenting himself to police.
He was released on police bail.
They are looking at the contents of a social media video showing an incident at the end of the match.
We are working hard to understand the sequence of events depicted in the video and have interviewed a suspect.
We would like to speak to any other witnesses who haven't come forward yet.
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