A 42-year-old mother has been arrested after the bodies of two boys, aged nine and 11, were found inside a Blue Mountains house.

The bodies of the boys, believed to be brothers, were discovered inside the home in Faulconbridge, north-west of Sydney, by a family member on Tuesday afternoon.

A major investigation has been launched. It has not been revealed how they died.

Police said the boys’ mother was taken to Westmead Hospital and was under guard in a stable condition.

The father, who has access to the property, contacted police and is helping with the investigation, said Blue Mountains commander Superintendent John Nelson.

Nelson said the mother was suffering “a number of injuries”.

“It is a tragic scene and our police are acting professionally in dealing with that matter,” he told media at a press conference on Tuesday afternoon.

“Our focus is coming to the bottom of what has happened in these tragic circumstances.”

NSW Police Commissioner Karen Webb said officers were called to the property on Chapman Parade about 12.40pm amid concerns for the welfare of a woman and two children.

“Police attended a short time later and discovered the bodies of two children, two boys, one aged nine and 11,”she said.

“The female has been transported to hospital, and she is under police guard in hospital and she has been arrested.”

Webb said there was no ongoing threat to the community and they were not looking for anyone else in connection with the incident.

Blue Mountains Police Area Command is investigating the circumstances of the deaths, assisted by detectives from State Crime Command’s Homicide Squad.

Anyone with information about the incident is urged to contact Crime Stoppers on 1800 333 000 or at nsw.crimestoppers.com.au.

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