Thousands of people rushed to escape a massive wildfire charging across California's tinder-dry Sierra Nevada foothills and another out-of-control fire that broke out in Northern California, injuring four firefighters.
The northern fire began in Lake County, 160km north of San Francisco, and grew to about 39 sq km in just a few hours, the California Department of Forestry and Fire Protection said.
The blaze has since exploded to more than 262 sq km amid triple-digit temperatures and land parched from several years of drought. A thick layer of smoke kept air tankers and helicopters from flying yesterday.
The fire forced the evacuation of two towns as well as residents along a 56km stretch of State Route 29.
The firefighters were airlifted to a hospital burn unit, where they were listed in stable condition, department spokesman Daniel Berlant said.
The fire so far has destroyed 86 homes, 51 outbuildings and was threatening about 6,400 more.
"I lost my business - it's all burned up - my shop, my house, 28 years of living," said Joe Thomas, who lives near Mountain Ranch. "I got to start all over. It's depressing."
A choking fog of smoke and ash turned California's grassy, tree-studded Gold Country an eerie white. Away from the burned-out cars and smouldering remains of homes, Annette Stout and other residents who fled rested at evacuation centres.
"I grabbed my cats, their carriers, important papers, my husband's death certificate and his ashes," said Mrs Stout.
California Governor Jerry Brown declared a state of emergency and more than 3,850 firefighters were assigned to the blaze. Its cause is under investigation.
Meanwhile, new evacuation orders were issued for the largest wildfire in the state, threatening to sweep through an ancient grove of Giant Sequoia trees. The fire, sparked by lightning on July 31, has charred 521 sq km, according to the latest fire map released by the US Forest Service.
In a fight to save the trees, firefighters cleared brush around the Grant Grove and set prescribed burns to keep the flames from overrunning it. By yesterday, the threat lessened when it became clear the backfiring and monitoring efforts helped protect the treasured trees, the Fresno Bee reported.
The grove is named for the towering General Grant tree that stands 82m tall. There are dozens of Sequoia groves in the Sierra Nevada, and some trees are 3,000 years old.