Chatham-Kent OPP now say two people have died as a result of the Sunday afternoon crash near Wallaceburg on St. Clair Road south of Wallaceburg.
William Hills, 88, of Sarnia, was pronounced dead at the scene of the crash, which took place between Border Road and Heritage Line.
Rose Hills, 87, also of Sarnia, succumbed to her injuries in hospital.
A third victim was treated and released.
The OPP, Chatham-Kent fire and EMS personnel attended the two-vehicle accident, which took place about 4:25 p.m. Sunday.
Police say the investigation is ongoing.
Anyone with information regarding this or any other incident is asked to call the OPP at 1-888-310-1122. Should you wish to remain anonymous, call Crime Stoppers at 1-800-222-8477 (TIPS) or leave an anonymous online message at www.catchcrooks.com where you may be eligible to receive a cash reward of up to $2,000.