People were sought after violence and racist chanting

The Independent Police Complaints Commission (IPCC) probe has been sparked by complaints from the public.

One person was bitten by a dog and had to spend several days in hospital.

The trouble followed a game between Stoke City and Birmingham City on 19 February. Police have made 17 arrests following the violence.

Police conduct

The IPCC will look at the overall strategy by officers from Staffordshire Police, the conduct of individual policemen, and the use of police dogs.

John Crawley, commissioner for the West Midlands, said: "The tactics police employ for crowd management at large events can be critical, particularly on occasions when public disorder situations arise.

"Violence at football matches is no longer common place and this is due in part to appropriate policing of large crowds and the greater confidence the public have in the police."

The IPCC needed to make sure police tactics did not contribute to the violence, he added.