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SYDNEY - A woman is under police guard in hospital today after a triple stabbing in Sydney's south-west, which killed a father and daughter and wounded the girl's mother.
A police spokesman said officers had not yet received medical clearance to speak to the woman, who was found walking in a street with bloodied hands soon after yesterday's incident.
The 25-year-old woman was picked up by Bankstown Highway Patrol on Uranus St in Revesby, not far from the home in Hydrae St where police had been called to a domestic dispute moments earlier.
The alarm was raised by a neighbour about 3.50pm (5.50pm NZT).
"Police were called to a house ... after reports of an altercation," a NSW Police spokesman said today.
"Initial inquiries show all parties involved in the incident are from the one family."
Police are yet to confirm the woman under guard is a daughter of the man killed.
They have said the man is believed to have been aged 53 and the dead girl is believed to have been 15.
Officers entered the home about 4pm and found two bodies inside.
"While formal identification is yet to be conducted, it is believed the two victims are father and daughter," the spokesman said.
The 52-year-old mother, who suffered knife wounds to her upper body, had run to a neighbour who alerted police.
She was taken to hospital for medical assessment and treatment for minor injuries.
Police, who are unsure of a motive for the attack, say they are investigating the psychiatric history of the woman under guard in hospital.
Post mortems will be conducted today on the bodies of the man and the girl.
Specialist police, including the State Crime Command's Homicide Squad and Forensic Services Group, are investigating.
- AAP