The Perth man charged with killing five members of his own family stayed with their bodies “for some days” according to police.
Anthony Robert Harvey, 24, is accused of killing his partner 41-year-old Mara Lee Harvey, two-year-old twins Beatrix Mae Harvey and Alice Esther Harvey, and three-year-old Charlotte Kate Harvey last Monday.
He is alleged to have then stayed in the Perth home overnight.
Mara’s mother Beverley Quinn, 73, was reportedly killed the following morning on Tuesday when she arrived at the house.
In a press conference on Monday afternoon, Western Australia Police Commissioner Chris Dawson would not confirm the exact times of death.
But he described the horrific scene police attended as “an absolute tragedy” in which they were “confronted by a situation that no person should have to face”.
Whilst a definitive cause of death was yet to be established, Comm Dawson said prosecutors would allege a “blunt instrument” and knives were found at the scene.
“We’re not alleging that any firearm was used. We’re alleging that several weapons were used,” he said.
“Those matters are facts before the court now. I can’t give a definitive cause of death.
“We’re still working with pathologists and forensics in terms of that.
“What we are alleging is that a blunt instrument and knives were used to cause the death of the persons at the house.”
It is believed Harvey may have stayed at the house for some days after the killings before heading north and showing up at a police station in Pannawonica, about 1400km north of Perth, on Sunday.
He then gave police information which led to the discovery of five bodies at the house shortly afterwards.
Comm Dawson said police discovered the bodies of Mara and Ms Quinn in the kitchen, and the children in other rooms of the three-bedroom property.
The family were not known to police prior to the tragedy and Comm Dawson would not comment on any mental health issues associated with the accused.
Mr Harvey appeared before a magistrate in Perth via a videolink on Monday afternoon charged with five counts of murder.
The family of the victims are expected to release a statement on Monday evening.