Man dead, infant fighting for life after collision in western Sydney

A man is dead and an infant child fighting for their life after a collision in Sydney's west.

At about 7.45pm overnight, police were called to Carlisle Avenue in Mount Druitt.

They found a 57-year-old man, a pedestrian, with life-threatening injuries.

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He was carrying a one-year-old child at the time of the collision.

The man was treated by paramedics but died at the scene.

A short time later, a man believed to be the infant's father arrived at Mount Druitt Hospital with the child.

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The child was taken to Westmead Children's Hospital in a critical condition.

The driver of the car, a 37-year-old woman, was taken to hospital for mandatory testing and is assisting police with inquiries.

An investigation is underway and a report will be prepared for the coroner.

Anybody with information or dashcam footage is urged to contact Crime Stoppers on 1800 333 000.

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