North Yorkshire Police said today that it wants to hear from any witnesses to the altercation, particularly a woman who with her two young children at the time.
The assault happened on The Stray near to St Winifred’s Avenue at around 4pm on Sunday, July 1.
It involved a group of teenage girls who were sitting together when a fight broke out between a 16-year-old and a 15-year-old.
A spokesman said: "We are requesting the public’s assistance to help establish the full circumstances surrounding the incident.
"In particular, police would like a potential witness to come forward, who is described as a woman with very blonde hair and pushing a buggy. The woman had two young children with her and may have seen the incident."
Anyone with information is asked to email [email protected] or call 101, select option 2, and ask for Beth Crawford-Evans.
Information can also be passed on anonymously via Crimestoppers on 0800 555 111.
Please quote the North Yorkshire Police reference number 12180118108.