An elderly passenger has died after she was critically injured in a crash on Friday.

The 88-year-old woman was travelling on the Hunter Expy at Greta, in the Hunter Region of NSW, when the SUV she was in collided with a second SUV about 5.20pm.

Her car rolled several times, according to NSW Police.

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Both she and the driver of the car — a 61-year-old woman from Bonnells Bay — were trapped in the wreckage for about an hour.

The 88-year-old woman was airlifted to John Hunter Hospital where she later died, police said on Saturday.

The 61-year-old woman was taken to the same hospital in an ambulance.

The driver of the other SUV involved, a 63-year-old woman from Aberdeen, was uninjured.

She had been driving ahead of the other car at the time of the crash, and stopped nearby after the incident.

Investigations are ongoing and anyone with information about the incident are urged to contact Crime Stoppers.

A report will be prepared for the coroner.