A mining structure was reported destroyed Thursday as the American fire continued to grow.
The fire, which began Saturday afternoon in the Deadwood Ridge area northeast of Foresthill, was reported 35 percent contained Thursday evening and has burned 5,420 acres.
Jane LaBoa, a public information officer with the U.S. Forest Service, said the mining structure that burned was in one of the area's historic mining districts, but officials have not disclosed the specific location.
The fire is not threatening Foresthill or other communities, and there have been no evacuations.
Effective today, an emergency closure order is in place for National Forest System lands within and adjacent to the fire.
A map of the closed area is available at Tahoe National Forest offices and online at www.fs.usda.gov/tahoe.
LaBoa said the closure area does include any campgrounds or major recreation spots. But people visiting recreation sites in Placer County and the Lake Tahoe area can expect smoky conditions.
A total of 1,226 people are currently involved in the firefighting effort. Officials said two minor injuries have been reported.
A 10,000-gallon water tank and 10,000-gallon mobile retardant plant to aid helicopter suppression activities have been established at the Blue Canyon Airport, just south of Interstate 80.
Call The Bee's Cathy Locke, (916) 321-5287.