A prison officer was taken to hospital with minor injuries following last night's riot at HMP Hewell in Redditch.
The incident has now been referred to the police.
It is understood inmates were refusing to follow prison officers' orders and were trying to cause damage to one of the wings in the category B jail.
An incident involving a small number of prisoners took place on Saturday 22 July.
The incident came to an end around midnight on Saturday when authorities regained full control of the wing.