The Latest: Wildfire in Gold Country destroys 86 homes

Officials reported slight progress in battling the fire, saying it was 15 percent contained despite a thick layer of smoke that grounded air tankers and helicopters from flying all day.

Cal Fire spokesman Daniel Berlant says the evacuation order has expanded to include Middletown, a town of 1300 about 8 miles southeast of Cobb, as well as residents along State Route 29 from Clear Lake to Calistoga.

Authorities say four firefighters have suffered burn injuries while battling a fast-moving wildfire that broke out in Northern California and forced the evacuation of a town.

California fire officials say a fire in Lake County quickly spread to 400 acres prompting the mandatory evacuation of the town of Cobb.

Cal Fire says mandatory evacuations have also been ordered for High Valley Road, Bottle Rock Road, Harbor Hot Springs and Big Canyon Road.

Authorities say helicopters and air tankers are ready to fight a massive blaze threatening Northern California mountain towns but a thick layer of smoke has kept them on the ground.

California Department of Forestry and Fire Protection spokesman Mike Mohler says high temperatures and low humidity have complicated the firefight southeast of Sacramento.

On Saturday, she was in Angels Camp, a quaint town made famous by a Mark Twain story, after spending much of the night rescuing her neighbors' four horses and several cats from their home in Mountain Ranch in the foothills southeast of Sacramento.

At Angels Camp, a quaint town made famous by Mark Twain's "The Celebrated Tale of the Jumping Frog of Calaveras County," incident commanders huddled behind a pickup truck loaded with maps assessing the fire's progress as a line of horse trailers lined up near a corral with about two dozen horses.