The Mills Canyon fire near Entiat doubled in size in 24 hours to 10,000 acres, officials said. The fire was reported Tuesday.
Evacuation orders have been issued for more than 100 houses. Herds of sheep and orchards were also endangered by the fire.
A 30-mile stretch of highway 97A between Entiat and Wakane was closed because of the blaze.
Officials said several hundred firefighters were trying to contain the fire, using
helicopters and air tankers as well as equipment on the ground.