Camera IconThe three children are all believed to be under the age of five years old. Credit: Tim Pascoe NewsWire/NCA NewsWire

One child has been killed and three others are in a critical condition after a brutal stabbing.

Around 12.45pm on Sunday, NSW Police received reports of a stabbing in the Blue Mountains.

Three children, all believed to be under the age of five, and a woman in her 40s were found in a vehicle on Waratah Road, Valley Heights.

All three were suffering from stab wounds.

When police officers arrived at the scene, several members of the public were providing medical assistance to the victims.

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One of the children was deceased.

Two others and the woman were treated at the scene before being taken to hospital.

All three remain in a critical condition.

Their identities have not yet been revealed.

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A crime scene has been established and an investigation is underway.

Police said that they were “not looking for any other people at this time”.

Anyone with any information is being urged to contact Crime Stoppers on 1800 333 000.

More to come...

If you or someone you know is experiencing family violence, phone 1800 RESPECT (1800 737 732) or the Crisis Care Helpline on 1800 199 008. Lifeline: 13 11 14.

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