A 24-year-old man has been charged with the alleged murders of five people, including a mother, her three children and their grandmother.
Mother-of-three Mara Quinn was among the victims of the alleged mass killing.
The West Australian reports, Ms Quinns daughters, Charlotte, 3, and two-year-old twins Alice and Beatrix, along with their grandmother were found dead at the Coode Street home on Sunday.
Police arrived at the property after the man presented himself at Karratha Police Station.
Homicide Squad detectives have since charged the 24-year-old man from Bedford with five counts of murder.
He will appear via video link in the Perth Magistrates Court today.

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