A man pushed a 51-year-old woman onto her back and straddled her during an attempted sexual assault in Noble Park earlier this month.
Dandenong sexual offence and child abuse investigators said the woman was walking south on Bloomfield Road between 1-2am on June 9 when the man attacked.
The woman escaped after the attacker was distracted by an approaching car. The man fled south on Bloomfield Road and west into Wachter Reserve.
He is described as Caucasian, in his late 20s-early 30s, 173-178 centimetres, of medium build, and with a fair complexion and dark straight hair just above shoulder length. He was wearing long pants and a long-sleeved top.
Anyone with information about the assault can call Crime Stoppers, 1800 333 000 or visit crimestoppers.com.au.
