A police officer wears a mask while controlling a roadblock near a wildfire in Fort McMurray, Alberta, Canada on Thursday. Raging wildfires in the Canadian province of Alberta moved south, forcing three more communities to evacuate and an emergency operations center to move again.

Volunteer Marlee Hildebrandt washes beds with her daughter, Oakley, on her back as she helps evacuees from the Fort McMurray wildfires at the Bold Center in Lac la Biche, Alberta, Canada, on Thursday.

People stop to take photos of a wildfire south of Fort McMurray, Alberta, Canada, on Thursday.

Evacuees from the Fort McMurray wildfires look through donated goods and clothing at the Bold Center in Lac la Biche, Alberta, Canada, on Thursday.

An evacuee, second from left, from the Fort McMurray wildfires speaks on a cell phone at the evacuation center in Edmonton, Canada on Thursday. Three more communities were evacuated and an emergency operations center moved again, taking it far from the devastated oil sands city of Fort McMurray.

Evacuees from the Fort McMurray wildfires arrive at the evacuation center in Edmonton, Canada, on Thursday.

A helicopter flies past a wildfire in Fort McMurray, Alberta, on Wednesday.

Smoke rises above trees as a wildfire burns in Fort McMurray, Alberta, on Wednesday.

Evacuees watch the wildfire near Fort McMurray, Alberta, on Wednesday.