The police said on Saturday that the structure, a tourist attraction for decades, was probably not salvageable. A man was arrested in connection with the blaze.

© Kerstin Joensson/Agence France-Presse — Getty Images

Smoke from the blazes, blamed on destructive agricultural practices, has sickened hundreds of thousands and blanketed neighboring countries.

© Dita Alangkara/Associated Press

Prime Minister Mark Carney said the “violent, fast-moving” fire on Saturday in Alberta was one of the worst tragedies for Canada’s armed forces in peacetime on Canadian soil.

© Jennifer Gauthier/Reuters

The defense minister said people were killed and injured at a base in Alberta, but officials did not offer details on the cause.

© John Ulan/The Canadian Press, via Associated Press