Up to five bodies have been found at a home in a suburb of Perth, just weeks after a triple fatality and a suspected family murder-suicide earlier this year.
A man aged in his 20s gave himself up to police on Sunday morning before officers went to a home on Coode Street in Bedford where the bodies were found.
Assistant Commissioner Metropolitan Region Paul Steel told reporters on Sunday police arrived at the home about 12pm (local time) to find women and children among the dead.
"Police have located the bodies of a number of deceased people including women and children. Whilst the scene is yet to be forensically examined it is believed up to five deceased are located at that scene," he said.
"It is a tragic thing when incidents like this occur. It does send a ripple through the community of Western Australia."
Mr Steel did not say how the people were killed or if any weapons were found and could not confirm the ages, genders and relationship of the deceased.
The tragedy comes after a 19-year-old man was charged with murdering an eight-year-old boy, a 15-year-old girl and their mother at Ellenbrook in July.
At the time of the incident, Mr Steel said it was "potentially the most horrific crime scene he has ever been called to".
In May another family was torn apart as four children aged eight to 14 were killed near WA's Margaret River. Peter Miles, 61, is suspected of shooting dead his 58-year-old wife Cynda, their daughter Katrina, 35, and her children - daughter Taye, 13, and sons Rylan, 12, Arye, 10, and Kadyn, eight - at their farm in Osmington.
Mr Steel said on Sunday the forensic police and the homicide squad were undertaking a "meticulous" investigation of the Bedford crime scene which "could take a number of days".
It is yet to be determined how long the bodies had been there, he said.
The man remained in custody on Sunday night and is being interviewed by police.
There are no ongoing concerns for community safety, Mr Steel said.
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Australian Associated Press