The two campers who started the fire have been detained, Carson City Sheriff Ken Furlong told the Reno Gazette-Journal.
The Humboldt Toiyabe National Forest said in a tweet Wednesday morning that the 500-acre fire, dubbed the Voltaire Fire, was 15 percent contained.
Carson City Fire Chief Sean Slamon said firefighters had a tough time with the fire Tuesday night since they didn't have air support.
The Associated Press contributed to this report.