Police Detective Senior Sergeant Kim Libby said police had since recovered the vehicle involved in the incident.
"Police have spoken to the registered owner of the vehicle and are continuing enquires to identify the driver.
"A forensic examination of the vehicle will be carried out today. Police want to thank those members of the public and witnesses who came forward with information about the incident."
The elderly woman was now in a stable condition in hospital and recovering in a ward.
A police spokesman yesterday said the roundabout near where the hit-and-run occurred is narrow, with no proper signage or barriers, so people drive through the area as if it were a road rather than a roundabout.
Auckland Transport's media relations manager Mark Hannan confirmed the speed limit was 50km/h in the area.
A person working nearby claimed the woman had been struck while she was using the pedestrian crossing.
"Police were at the scene very quickly," the worker said.
A news photographer who was on the scene after the collision described the traffic around the mall and Kmart as "chaotic" but said police were controlling it "the best they can".
