Homicide squad Detective Inspector John Potter told a media conference this afternoon it was believed the woman, 29, knew her attacker.

"There was no sign of forced entry. At this stage doesn’t appear to be a burglary gone wrong," he said.

PHOTOS: Doveton Street murder

The woman's four-year-old son was inside the Doveton Street South home when she was killed with what the detective described as "blunt force trauma".

Detective Inspector Potter said the boy saw a man but said he did not know him.

He could offer no real description beyond "darkish clothing".

"At this time we haven’t been able to determine exactly who the man was in the house or at what time," he said.

Detective Inspector Potter said the woman had separated from her partner and all but ruled him out as a suspect in the killing.

"The woman has had a partner in the past, she was not living with that person ... we have followed those lines of inquiry pretty thoroughly," he said.

The woman's body was found by relatives at 10.40am on Saturday when they arrived to do some gardening.

Detective Inspector Potter made a renewed call for any witnesses to come forward.

"If somebody saw anything in vicinity....no matter how irrelevant they may think it is, can they please call Crime Stoppers," he said.

Detective Inspector Potter said the woman and boy had been out earlier on Friday, but returned to their home at 8.30pm.

The murder occurred sometime after that.

He said the public could hold the key to solving the brutal crime.

"We're working on some lines of inquiry... (but) clearly somebody knows what's happened here," he said.

"This is a brutal crime to a woman in her own home, so we're very keen to find out who's responsible."

Detective Inspector Potter also made a plea for the man to hand himself in.

"If this man isn't responsible...if somebody was in the house and had nothing to do with this particular incident, they should come forward and tell us about it," he said.

The boy is being looked after by family members as police continue to investigate the circumstances of the death.

On Saturday, homicide Detective Senior Sergeant Dave Snare said the death was being treated as a murder. 

“There are obvious signs of an injury, an incident has occurred. She has sustained a severe injury, which appears to be violent,” he said.

A relative of the woman, who was visibly distressed, said she “felt sick” after finding out about the incident. 

“I don’t know any more, I just wanted to know what’s going on,” she said.

Another woman, who said she knew the victim, immediately broke down and began sobbing after finding out about the incident.

Police doorknocked local residents and relatives to find out if they had information about the attack.

Two properties, including a podiatrist’s next door, were cordoned off as forensic police collected evidence from the crime scene.

They took photos of a white Toyota Hilux, which was parked at the back of a gravel driveway connecting both houses at the rear.

Neighbours spent much of the day standing outside their homes on Doveton St South watching the drama unfold. 

Nearby resident Mark Kelava said despite the busy nature of the street the neighbourhood was typically very quiet.

“I’m in shock, that’s all I can say,” he said.

“Normally this is a friendly street. We all know each other.”

Patricia Hood, who lives across the road from the house, said the people who lived there were quiet and moved in only last year.

“I got a shock when my husband woke me up and said ‘the coppers are out here’,” she said.

“We didn’t think this would happen so close.” 

Other locals looked unfussed by the police and media presence, with one woman getting on with painting the windows on her house.

At one house, children continued to play on a trampoline, seemingly unaware of what had taken place across the street. 

In another front yard a group of neighbours gathered for a beer as they met to speak about events.

Police cordoned off parts of the street as cars slowed down to have a look at what was happening.

When asked if residents should take precautions after the attack, Detective Senior Sergeant Snare said people should always lock their doors. 

Neighbour Ian Dwyer said he wasn’t concerned about the safety of the area.

“We don’t know what’s happened across the street, but we’re not concerned about the street or anything like that.” 

Paramedics were initially called to the scene with reports of an assault, however Ambulance Victoria referred requests for information to police.

Anyone with information is asked to phone 1800 333 000.