The homicide squad is investigating after three toddlers, their mother and grandmother were found dead at a home in Perth's north-east.
"The man now assisting police remains in custody, no charges have been laid at this time", police said in a statement.
Specialist forensic police are expected to continue a meticulous examination of the crime scene on Monday.
"Police have located the bodies of a number of deceased people including women and children", he said but would not say how they died or if any weapons were found.
A man in his 20s turned himself to a regional police station on Sunday, ahead of police going to the home where they discovered the bodies around midday.
In a statement via 7 News Melbourne, Metropolitan Region Assistant Commissioner Paul Steel confirmed the "tragic event".
POLICE have charged a 24-year-old man from Bedford with five counts of murder over the deaths of two women and three children.
Another neighbour told WA Today she didn't know the home's occupants personally, but would often wave and say hello as she walked past.
Police at the scene in Bedford, WA.
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Ms Harvey and Mr Harvey both used to work for a Sino Steel Pilbara mine, and Ms Harvey sold some of her properties to help her partner start up a business.
"It's just really sad that something like this can happen in such a quiet neighborhood, it's horrid on every level. poor children", Maria Manfredini, a resident in the area, told 9News.
"This is a tragic event that will have no doubt have an impact, not only on the family and friends of the deceased, but for the whole of the community, those first responders who were faced with attending a scene with multiple deceased people".
"Just a normal family, you would never imagine anything like that happening", he said.
"We're all in complete shock".
Then in July, a mother and two children were found dead in a house in Ellenbrook, in Perth's north. He was questioned, but it's unclear if he's related to the victims and no charges have been laid yet.
A grandfather shot dead his wife, daughter and her four children in murder-suicide in May.
"The scene has not yet been forensically examined so the exact number of adults and children is actually unknown to me", Steel said.
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