Investigators have been told a female was approached was approached just after 6pm by an unknown male as she left a public toilet on Lonsdale Street.

The male sexually assaulted the female before she managed to push him away and call out to a friend who was nearby.

He then ran off and was chased for a short time by the victim’s friend.

The male has been described as 185cm and aged in his late teens with a medium build and brown wavy hair.

He was wearing a black hooded top with white writing on the chest and grey track pants.

Anyone with information, including any businesses or residents in the area who may have CCTV footage, is urged to contact Crime Stoppers or submit a confidential report online at www.crimestoppersvic.com.au.