Man wanted over inner Melb sex assault

An image has been released of a man wanted over the sexual assault of a woman in inner Melbourne earlier this year.

The woman aged in her 20s was walking along Gatehouse Street in Parkville about 2.35am on March 28, when she was bear-hugged from behind by a man near the intersection with Bayles Crescent, police say.

The pair fell to the ground and the man sexually assaulted the woman who screamed, alerting neighbours as the attacker tried to cover her mouth.

The woman escaped and ran to a nearby property where residents called police, but a subsequent search, including the air wing, couldn't find the man and several people of interest have since been ruled out.

The man is described as aged between 25 and 35, with olive skin, muscular build and of "average height", and wearing a blue or grey hooded jumper, grey jeans and runners with white soles.

Detectives will set up an information caravan in Gatehouse Street from 10am until 2pm on Wednesday and have urged anyone with information to attend or contact Crime Stoppers on 1800 333 000.