A 24-year-old man was charged with five counts of murder after three young girls, his mother and grandmother were found dead in a house in Perth.
The bodies of Mara Quinn, in her 40s, her three-year-old daughter Charlotte, her two-year-old twins Alice and Beatrix, and her grandmother were found in a house in Bedford, east of Perth, on Sunday.
It comes after the shooting deaths of three adults and four children, all from the same family, in Osmington in WA regional in May, and the murder of a mother and her 15-year-old daughter and her eight-year-old son in Ellenbrook. , in the northeast of Perth, in July.
The man from Bedford surrendered himself at the Karratha police station, about 1500 kilometers north of Perth, prompting the police to visit the house on Coode Street, where they discovered the bodies around noon.
It is believed that man also lived in the home.
He will appear at the Magistrates Court in Perth via a videoconference of the Magistrates Court of Karratha later on Monday.
Homicide detectives and specialized forensic police continue to search the home for evidence.
"Depending on the size of the crime scene, it will take a period of time and it could be a number of days," deputy commissioner of the Metropolitan Area Paul Steel said Sunday.
A bouquet of red roses with a card that says "Rest in peace, neighbors" has been placed against a lamppost near the house.
According to her Facebook page, Mara Quinn got engaged in August 2014 and had her first child in March 2015.
The records show that she bought the family home in 2008.
A young father, who is building a house nearby, told AAP: "I have a two-year-old girl, I can not rationalize anything that can make someone do it."
An elderly woman who also lives nearby said: "I do not know what will come to this world."
A couple living a few doors down the street said he did not know the family, but he was horrified when the police knocked on his door and told them what had happened.
An elder who has lived in the neighborhood for decades said it was generally quiet.
"It's usually a quiet place," he told AAP.
Deputy Prime Minister and Health Minister Roger Cook said it was not yet known if there was a common cause among the three tragedies, but added that mental health was his most challenging portfolio and that the situation seemed to get worse.
"We have limited resources, we are constantly looking for new ways in which we can apply those resources to provide the right level of support," Mr. Cook told reporters.
"I want everyone to hug their children, hug their family today, this is a horrible event and it's very disturbing."
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