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.

Southern suburbs man claims $2.5 million Lotto win
Wanted man possibly in Mandurah or Rockingham areas
Big fines for three fisherman caught with too many mullet, undersized crabs
Brand new six-storey hospital to replace Peel Health Campus
Drug and Firearm Squad swarm Meadow Springs home
Wanted woman known to frequent Mandurah, Rockingham, West Pinjarra areas
Waikiki Beach Hotel to go ahead after liquor licence approved
Man found critically injured outside Baldivis pub
Dawesville man charged with 38 child sex offences