A 32-year-old man has been charged with murdering his parents and youngest brother and trying to kill another brother.
A mother, father and their adult son have been killed in what police allege was a gruesome triple murder in Sydney's south-west.
Charles Feng and Ruvena Lam's oldest son, Jacky Feng, who was arrested outside their Rosemeadow home, has been charged with murdering his parents and youngest brother and trying to kill another brother.
Senior police said officers were confronted with a "very grisly crime scene".
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At 1.30am today officers found 65-year-old mother Ruvena Lam injured and started CPR before discovering the full scale of the tragedy on Juliet Close.
"Police then went inside the house, and found a 64-year-old male who was still alive with serious blunt force head injuries," Superintendent Grant Healey said.
That man was 64-year-old Charles Feng.
Neither he nor his wife survived.
Police then found their youngest son, 25-year-old Justin, dead in the granny flat.
"This is an incredibly rare incident and it is incredibly tragic," Healey said.
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A third brother, aged 30, was injured but was able to call Triple Zero.
He is out of hospital but unable to go home.
Police alleged the 32-year-old accused left the scene this morning before officers arrived but came back an hour later and was arrested.
He was charged this afternoon with three counts of three counts of murder (DV) and one of attempted murder (DV) and refused bail to appear before Campbelltown Local Court tomorrow.
Forensics are still searching for multiple alleged murder weapons including a hammer.
They towed away the suspect's car, as they hunted for a motive.
Healey said emergency services were faced with a "horrendous" scene.
"They were confronted with a very bloody scene," he said.
He said the family was not well known to police and never for domestic violence incidents.
"This is a very tragic incident, there was no way for us to predict this kind of thing to occur," he said.
Support is available from the National Sexual Assault, Domestic and Family Violence Counselling Service at 1800RESPECT (1800 737 732)
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