A 15-year-old girl was assaulted in the toilets at Northumberland College at around 12.50pm on February 25.
The victim was approached by a girl who grabbed and pushed her. The attacker is thought to have left in a small blue car. The offender is described as 17 or 18, of plump build and around 4ft 11ins tall. She had black shoulder length hair in a bob style with blonde tips. She was wearing a black padded coat with a fur-lined hood and spoke with a Welsh accent.
Anyone with information should contact police on 101 ext 69191.