Update 3:50 p.m:
RCMP advise the scene has been cleared and the road is now open in all directions.
MD OF OPPORTUNITY - A single vehicle rollover involving a tanker truck has shut down traffic in both directions on Highway 813, north of Calling Lake.
Athabasca RCMP advise they are currently on the scene of the accident on Highway 813 at mile marker 91 and that no injuries have been reported.
Traffic will be blocked in both directions while emergency crews clear the scene, until further notice.