A 15-year-old was left battered and bruised by a two-hour ordeal at the hands of another teenage girl.
Part of Kathleen's hair was pulled out during the attack
Kathleen Ginty, of Altrincham, Greater Manchester, had her hair singed, was stamped on and had her head smashed on the pavement in the attack on 7 July.
Her ordeal began in Kirkup Gardens in Wythenshawe but continued elsewhere as she was moved around by the girl, who told onlookers they were friends.
Police want to trace witnesses who may have seen her with her attacker.
Kathleen was taken to Wythenshawe Hospital after the attack suffering from two black eyes, a cut lip and bruising.
Her mother Karen Fletcher, 41, said: "I knew something was wrong when she didn't come home.
"She would normally ring to tell me if she was going to be late. I kept calling her mobile, but it was switched off.
"When I got to the hospital, my older daughter Vicky was already sitting by her bed. I didn't recognise her."
Mrs Fletcher said her daughter had been left depressed and feeling low since her ordeal.
She was set upon after being accused of trying to "steal" one of her attacker's friends.
After the incident in Kirkup Gardens, a third girl - who took no part in the attack - joined them and they boarded a number 11 bus.
They got off the bus at Greenbrow shops, near Firbank Road, and went into Baguley Park where Kathleen was assaulted again.
She was then taken to a wooded area near Chalford Road, where she was kicked and stamped on. She managed to escape after she was taken to a nearby house.
Det Con Shagufta Khan, of Greater Manchester Police said: "This was an absolutely horrific attack in which the victim was beaten and humiliated to a sickening degree.
"We cannot tolerate this kind of violence on our streets. We need witnesses to help us bring the attacker to justice."
A 15-year-old girl was arrested on suspicion of kidnap, wounding and robbery and later released on bail.