Emergency services were called to the Talawahl Rest Stop at Possum Brush about 15 kilometres south of Taree after concerns were raised for the man’s welfare about 10am today.

When police officers arrived, they found a man on the ground next to a vehicle in an “unresponsive” condition and started performing CPR.

NSW paramedics also went to the scene, but the man could not be revived.

The man has not yet been formally identified.

A crime scene will be established and forensically examined.

Police are still confirming the man’s identity.

“Police are still working to determine what injuries he had,” Detective Acting Inspector Sam Brennan said.

The rest stop is expected to remain closed for the rest of the day.

Anyone with dashcam footage from the area on Wednesday or today has been asked to come forward.

Police also urged members of the public to avoid stopping on the side of the Pacific Highway over traffic dangers.