 Police and stewards were hit with missiles |
Staffordshire Police said they believed a football match where rival fans clashed was "low-risk" and therefore only provided a small police presence. Trouble began at the Britannia Stadium in Stoke-on-Trent at the end of a match between Stoke City and Hull City when the visitors scored a late equaliser.
Officers and stewards were pelted with missiles including glass bottles and bricks outside the ground.
Ten people were arrested for various offences and later released on bail.
A spokesman said only around half of the matches in Stoke are attended by police, with this particular match deemed low-risk by both the football club and police.
"The levels of police resources in attendance at matches in Stoke-on-Trent is carefully assessed and agreed with the clubs," he added.
Ch Supt Mick Harrison said: "All those involved in the disorder, whether those throwing punches and stones or those standing shouting abuse are responsible for the damage done to the reputation of both clubs.
"An investigation has now begun into the disorder, where evidence allows we will make further arrests."
All those arrested on Saturday are from the Staffordshire area.
Four teenagers were arrested for threatening behaviour and a fifth for assault.
Two people, aged 24 and 25, were held for affray, a 30-year-old for pitch encroachment and a 31-year-old and 45-year-old for disorderly and threatening behaviour.