Staff tried to close the station while the emergency was unfolding, but customers kept pulling up, Singh said.
Senior Sergeant Jeremy Field praised service station staff for their efforts to resuscitate the stricken driver.
"It was good of the staff at the Service Station to assist with CPR," he said.
"The owner closed the station for a short period of time so staff could get counselling."
Z communications manager Jonathan Hill said it was a difficult time for staff at the station who swung into action and did their best to save the elderly driver.
Staff held first aid certificates and administered CPR until emergency services arrived.
"It's an incredibly sad time and our thoughts are with the young boy and his family," he said.
All staff would be offered counselling in the wake of the forecourt death, he said.
Police expected to name the deceased later today and the death has been referred to the coroner.