Boolaroo stabbing death: teenager charged with murdering 10-year-old sister in family home

A 17-year-old girl has been charged with murdering her sister, 10, after an alleged stabbing in the New South Wales Hunter region, with police saying the incident appeared to have come “completely out of the blue”.

NSW police said emergency services responded to reports of a stabbing at a home in Boolaroo, about 15km west of Newcastle, on Monday afternoon.

“My thoughts go out to the mother at home having lost a 10-year-old tragically and now … her other daughter is facing court allegedly responsible for killing the 10-year-old,” Det Supt Daniel Doherty told reporters on Tuesday.

“It’s a tragic circumstance. It’s hard to imagine.”

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NSW police earlier said in a statement that paramedics had treated the 10-year-old at the scene for multiple upper body stab wounds “however she died at the scene”.

The sisters were the only children in the family home, Doherty said.

Officers arrested the 17-year-old girl at the house. “She was taken to Belmont police station,” police said. “A crime scene has been established as investigations continue.”

The teenager was charged with murder and refused bail to appear at a children’s court later on Tuesday.

“There is no indications, from what information we have at the moment, to indicate why this occurred,” Doherty said on Tuesday.

“This is … one of those incidents that has happened, as far as we know, completely out of the blue. The circumstances will come out through the investigation but we will allege she [the older sister] was responsible, solely responsible, for the death of the 10-year-old.”