POLICE  are searching for a sex fiend who assaulted a youth listening to his iPod while at the scenic look out at Quarry Hills Park in Epping on Wednesday.

The victim, a 17-year-old from South Morang, told police he was struck from behind and knocked to the ground before being assaulted between 7.15am and 7.30am, Sergeant Creina O’Grady said.

While the teenager was dazed and lying on the ground, he was sexually assaulted by a man who struck him in the jaw, knocking him unconscious.

“The victim was found, still lying unconscious on the ground with his clothes in disarray, by a man and woman who immediately called an ambulance and police,” Sergeant O’Grady said said.

The teenager was taken to hospital with cuts and abrasions.

The offender was aged between 25 to 30, of Asian appearance, chubby build, with short brown hair which was noticeably longer in the front, a flat nose, pale-coloured skin and shaven legs.

At the time of the attack he was wearing a white T-shirt, blue shorts with black pockets and white slip-on shoes.

Sergeant O’Grady said Epping Sexual Offences and Child Abuse Investigation Team detectives were appealing for witnesses, including a man seen walking his dog in the area at the time of the offence.

This potential witness was aged in his 60s, about 170 centimetres, of solid build with sandy grey hair and was walking a golden brown labrador or similar dog.

Police are appealing for anyone with information to contact Crime Stoppers on 1800 333 000 or www.crimestoppers.com.au.