A wildland fire east of Jackson that prompted evacuations grew by a wide margin overnight.
The Butte fire, which started at 2:26 p.m. Wednesday near Butte Mountain Road, had burned 4,000 acres by Thursday morning, according to the California Department of Forestry and Fire Protection.
On Wednesday, when the fire was 3,000 acres smaller, containment was listed at 30 percent. But the rapid growth of the blaze overnight dropped containment to 20 percent.
Butte Mountain Road and Highway 26 from Happy Valley Road to lower Dorray Road were closed and evacuations were in effect for Amador Lane and the end of Electra and Charamuga Ranch Road.
The fire burned in the Mokelumne River drainage in Amador County and jumped the river into Calaveras County, according to a Cal Fire news release.
Fire officials said crews were contending with steep terrain and high temperatures.
Crews from Jackson Fire Department, Amador Fire Protection District and the U.S. Forest Service were helping to battle the blaze.
Fire crews on the ground were being assisted by air tankers and helicopters.
The U.S. Forest Service deployed two “super scooper” planes from South Lake Tahoe. The planes can carry up to 1,621 gallons of water.