Hundreds of northern California homes and businesses have been threatened after wind-driven wildfires broke out over the weekend, forcing thousands of residents to flee their homes throughout rural regions north of San Francisco.
The biggest fires continued to grow but that there were no reports of injuries or deaths, California's Department of Forestry and Fire Protection said on Monday.
About 3000 residents evacuated homes in Lake County, about 190km north of San Francisco. A wildfire there that was not contained at all grew to 31 square kilometres and destroyed a dozen homes and buildings, the agency reported.
Fire Battalion chief Jonathan Cox said more than 230 firefighters using helicopters, bulldozers and other equipment were battling the Lake County fire in a rugged area that made it difficult to get equipment close the blaze.
"It's kind of the worst possible combination," Mr Cox said.
Authorities also ordered residents to evacuate in Tehama County, about 32km north of San Francisco, where a wildfire destroyed multiple homes and businesses, while threatening 200 more.
Officials said that fire was 20 per cent contained. A nearby casino was serving as an animal evacuation centre.
Residents also fled a wildfire in Shasta County about 480km north of San Francisco.
No cause has been determined for any of the fires.
