A 42-year-old woman has been charged with murder and attempted murder following a serious incident involving three children in the Blue Mountains region of New South Wales. Police were called to Waratah Road at Valley Heights, near Springwood, at about 12:45pm on Sunday after reports of people injured inside a parked vehicle.

Emergency services found a woman and three children suffering from stab wounds. The children were all under five years old. A five-year-old boy was found deceased at the scene, while two other children, aged one and three, were critically injured.

Members of the public who discovered the group contacted emergency services and provided first aid while waiting for police and paramedics to arrive. Ambulance crews treated the injured people before transporting the two surviving children to Westmead Children's Hospital.

The two younger children remained in a critical but stable condition, according to police and medical updates reported on Tuesday. The 42-year-old woman was also taken to hospital for treatment. Police allege that she had suffered self-inflicted stab wounds.

On Tuesday, the woman was charged during a bedside hearing at Westmead Hospital. She faces a murder charge relating to the death of the five-year-old boy and attempted murder charges relating to the two surviving children.

The charges represent allegations before the court and will be considered through the legal process. The woman has not been convicted of the offences.

Police had previously said the incident was being treated as a domestic-violence-related matter. Investigators have continued examining the circumstances surrounding what happened inside the vehicle and the events leading up to the emergency call.

The incident has affected the local community around Valley Heights and Springwood, with emergency services conducting a major response at the scene. Police have also been communicating with the children's father as investigations continue.

The two surviving children remain in hospital receiving medical care. Their condition is being closely monitored following the serious injuries.

The investigation remains ongoing, and police are continuing to gather evidence about the circumstances of the incident. Because the matter is now before the courts, further proceedings will determine the evidence and allegations in greater detail.

The case has drawn significant attention because of the ages of the children and the circumstances in which they were discovered. Authorities have urged the community to allow investigators to conduct their work while the legal process proceeds.

For residents in the Blue Mountains, the incident has also highlighted the importance of emergency assistance and the response provided by members of the public who contacted Triple Zero and assisted at the scene before emergency crews arrived.

Police have not indicated that there is any ongoing threat to the wider community connected with the incident. The investigation and court process will continue as authorities establish the full circumstances surrounding the deaths and injuries.