Updated

A wildfire fed by dry temperatures and strong winds raged toward four hillside communities Sunday in northern Los Angeles County (search), forcing several thousand people to flee their homes.

Authorities said 1,600 homes in Santa Clarita (search) had been evacuated since the fire began Saturday. Up to 800 homes were in imminent danger and authorities were taking precautions by evacuating all three canyons north of the blaze, said county fire spokesman Mike Brown.

Winds of up to 25 mph fanned flames toward homes in the communities of Fair Oaks Ranch and Via Princesa, and those on both sides of Sand Canyon just hours after officials had lifted an earlier evacuation, county fire inspector Edward Osorio said.

Earlier reports that the fire had jumped containment lines were later withdrawn.

More than 1,000 firefighters, along with water-dropping helicopters, battled the blaze amid dry conditions and temperatures in the 90s, and residents remained outside their homes Sunday night, officials said.

No injuries or structural damage was immediately reported from the fire, which began Saturday. It was one of several burning more than 40,000 acres in the state, from eastern San Diego County to Yosemite National Park (search).

About 90 miles east of downtown Los Angeles in Riverside County, fire officials contained 50 percent of a 3,600-acre fire. Full containment was expected Tuesday morning.

"We're continuing to improve lines, and we don't see much more growth in the fire," said Jim Boano, a spokesman for the California Department of Forestry.

Mandatory evacuation orders were lifted Sunday for about 500 homes, but voluntary evacuations were issued for another 200 homes, Boano said. The fire destroyed three single-wide mobile homes, 11 outbuildings and several vehicles.

The fire was started by someone who had been shooting target practice, officials said. The person, whose name was not released, was given a citation and may have to pay a portion of the firefighting costs.

A lightning-sparked wildfire in Yosemite National Park was being allowed to burn because slow-moving flames were cleaning the forest floor of debris that could have fed a more dangerous fire. The blaze has scorched at least 3,000 acres and forced the closure of several popular trails.

About 45 miles north of Los Angeles, an arson fire burning since Monday was 75 percent contained Sunday after blackening 16,800 acres. That blaze had destroyed three homes and five outbuildings. The fire had forced the evacuation of nearly 1,000 people from rural communities, but mandatory evacuation orders were lifted starting Friday.

In eastern San Diego County, a 8,867-acre fire that had destroyed two homes and four outbuildings was extinguished Sunday afternoon.

Elsewhere, fire crews in western Nevada started heading home Sunday after mostly containing an erratic fire that had destroyed at least 15 homes and briefly threatened the governor's mansion in Carson City. The wind-driven fire, which blackened nearly 7,600 acres along a four-mile stretch of the Sierra foothills, was 85 percent contained late Saturday and fire officials said it could be fully contained by Tuesday.