Two primary school pupils have been found dead in their mother's New South Wales home, discovered by their father in "a tragic scene".
The boys, aged nine and 11, were found about 1pm on Tuesday at a home in Faulconbridge in the Blue Mountains, west of Sydney.
Local police commander Superintendent John Nelson declined to speculate on what had occurred but said the boys' mother, aged 42, was under arrest in hospital.
He confirmed the father, who has access to the home but does not live there, found the boys and contacted police.
"It's a very tragic scene," Supt Nelson told reporters.
"The Blue Mountains is a very peaceful, community-minded environment so they will be genuinely shocked."
The boys had attended school on Monday and police are investigating their movement since then.
Their mother is being treated for injuries in Westmead Hospital under police guard. She was stable on arrival.
It was unclear whether the injuries were self-inflicted.
The mother was known to police for only minor matters and early inquiries had not revealed any history of violence, police said.
NSW Police Commissioner Karen Webb attended the local station to provide support to her officers, noting many had children the same age as the deceased.
Clinicians and support officers were on hand for police, while the boys' father was also receiving support.
"The older and more experienced you get in this job, things like this still cut to the core," she said.
"It's a tragic situation and certainly ... more will be known as the investigation unfolds."
There was no ongoing threat to the community and police were not looking for anyone else.
