Residents have been fleeing the fire since the weekend on the only road out of Fort McMurray, Highway 63, which runs north to the oil sands refineries and south toward Edmonton, the nearest sizable city, about 270 miles away. Vehicles jammed the highway as a haze of thick smoke made visibility difficult.

The evacuation ordered for Fort McMurray is the largest in the history of Alberta. Most evacuees set out for Edmonton or other places in the southern part of the province, but others headed for evacuation centers set up at the oil sands industry’s work camps, which usually accommodate workers from other parts of Canada.

Gas stations in Fort McMurray and along Highway 63 ran out of fuel, according to the CBC, and some evacuees were left stranded along the highway overnight.

Irony has run out of gas!