The 17-year-old victim, daughter of a police head constable, was seriously injured in the attack yesterday night, they said.
She was admitted to a private hospital and her condition is stated to be critical.
The victim is a student of Class 11 and also works part- time in a showroom. The incident took place when she was returning to her house in Surinder Nagar locality from work.
Police said a case has been registered against unknown persons.
The girl is not in a position to speak and her family is unaware whether she was being stalked, police said.