The Halstead Fire has already prompted the closure of several campgrounds and Forest Service roads since it was started by lightning Friday. The U.S. Forest Service on Tuesday said the fire had actively grown overnight and spread from 60 acres to about 3,700 acres.
A smokejumper crew retreated Sunday from the blaze in the Salmon-Challis National Forest after it was deemed too dangerous to battle on the ground. Firefighters are now trying to contain the blaze between Beaver Creek Road and a tributary of the Middle Fork of the Salmon River. (AP)