Wollongong police duty officer Acting Inspector Dan Richardson said, according to witnesses, the woman fell on the footpath near Towradgi Railway Station about 11.30pm. 

"A passing motorist heading west along Towradgi Road has stopped near the railway bridge overpass to render assistance," Insp Richardson said.

"It looks like another vehicle also heading west has either collided with the stopped vehicle, pushing it into the pedestrian or tried to take evasive action and one of the vehicles has struck the pedestrian, we’re just not sure at this stage."

Insp Richardson said the woman, who is believed to be 81, died at the scene. 

"As a result of that collision, the pedestrian has been struck and died," he said.

A crime scene was established and the Southern Region Crime Investigation Unit are investigating the incident. 

Towradgi Road was closed for most of the night, but has since reopened.