Hunt on for van driver who hit elderly man

The hunt is on for a driver who killed an elderly man in an apparent hit-and-run in Sydney's southwest.

On Wednesday afternoon, a 73-year-old man was opening the door of his ute to get in when he was hit by a white van travelling north along the road.

The man was fatally injured and died in the ambulance on the way to hospital.

The man has been named in media reports as Zac Andreou.

Police are hunting for the driver and have released CCTV footage of the white Toyota Hiace van they believe hit Mr Andreou.

The van may have damage to the front passenger side and police are calling for anyone with information to come forward.

His son Andrew Zacharia told News Corp he was inside the house during the hit-and-run and rushed outside to see his father on the ground.

"I saw him die in front of me," he said.

"How could someone do that and take off?"