It is believed, whilst Jason Clarke and family, who are Port Vale supporters, were leaving Vale Park, they were approached by a group of males aged between 20 and 40, when, amidst confusion eight year-old Freya was knocked to the ground.
Jason said; "All of a sudden Freya dropped to the floor and started screaming. I picked her up and asked her what had happened and she told me she had been punched in the face. She had a red mark under her eye and she was in a state but by the time I got her up the men had gone."
Pete Aston, football liaison officer for Staffordshire Police, said: "We have, together with our colleagues at Port Vale, been to visit the girl and her parents.
"We have taken more details of the incident and will review this information, together with CCTV to establish exactly what happened. The family are fully supportive of this action.
"Staffordshire Police treats every football game in the county as an individual operation. The appropriate level of policing and stewarding is determined in conjunction with the club."
Both Port Vale and Walsall have issued statements, a Vale spokesperson is quoted as saying; "The club is aware of the incident and our club safety officer has visited the family as part of an ongoing investigation with Staffordshire Police. Port Vale Football Club does not condone violence in any way and we regret that this incident has happened."
A Walsall Football Club spokesman added: "We have received a letter from Mr and Mrs Clarke and have now responded. We are investigating this incident and taking the matter extremely seriously."
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