Detectives investigating clashes between Leeds United and Derby County fans have issued pictures of men they are trying to trace.
Police said groups of fans were involved in a series of disorder incidents after the two teams met at the iPro Stadium in Derby on October 15.
Arrests were made after the match but officers from Derbyshire Constabulary are now appealing for help to identify several men they want to speak to in connection with the clashes.
A West Yorkshire Police spokesperson said: "A number of arrests were made after the fixture – which Derby County won 1-0 – but police still want to speak to several men.
"Images of five men, thought to be Leeds United supporters, have now been issued and Derbyshire Constabulary’s football intelligence officers are asking the public to help identify them.
"Anyone who recognises the men shown should call PCs Allan Guy or Rob Beeston on 101, or 0345 123 3333 if you are calling from outside Derbyshire.