Footage of the shocking incident shows the young victim being punched in the head by a teenage boy, knocking her to the ground.
A teenage girl then joins the attack, repeatedly punching the helpless youngster as she lays slumped on the floor, knocking her unconscious.
The distressing assault reportedly occurred at a funfair in the Hesketh Bank area at around 8pm on Saturday (May 21).
The girl’s mother – who wished to remain anonymous – said the incident has left her daughter bruised, shook up and unable to sleep.
She explained her daughter was attempting to walk away from a verbal argument when the boy ran up behind her and punched her.
“It’s shocking. Something needs to be done,” her mum said.
“You don’t want to let your kids out anywhere any more.
“These kids these days are going to end up killing each other.”
She added the incident had been reported to the police, but claimed they had not been interviewed or spoken to since.
“I rang the police to say I would see them on Monday, but they rang me back and said, ‘Sorry we’re really busy. It’ll have to be Tuesday’.
“I thought because my daughter had been seriously assaulted it would have been dealt with relatively quickly.
“She’s a child and I’m lucky to have her.
“He could have killed her.”
Lancashire Police said the incident had been reported to them and was “under investigation”.