She was walking her dog through a Wollongong park around 5.30 p.m. Thursday when the teenage girl was sexually assaulted at knifepoint by a teenage boy.

The unnamed girl, 15, was indecently and sexually assaulted before she was able to scream for help, the Daily Telegraph reported.

The teenage boy, 16, was caught and charged with sexual assault. Both teens are from New South Wales.

Police said someone who responded to the girl's call for help managed to detain the boy, who has been charged with three counts of aggravated sexual assault, four counts of aggravated indecent assault and one count of detain for advantage.

He was refused bail to face Port Kembla Children's Court Friday, the Telegraph reported.