Attempts by 900 firefighters backed by aircraft to halt the spread of a wildfire burning in rugged terrain in southwest Idaho have been unsuccessful with the blaze doubling to 14 square miles in size on Wednesday.
Officials say they've expanded a closure in the Boise National Forest and also started contingency plans to use State Highway 21 as a firebreak.
About 23 miles of the highway are closed from north of Idaho City to south of Lowman as firefighters remove trees and brush to reduce the potential for the fire to cross the road.
Managers gave no timeline for when the well-traveled route from southwest Idaho to vacation areas in central Idaho will reopen.
Officials say 10 structures are threatened and 35 people have been evacuated.