San Diego: Towering wildfires burned out of control across Southern California for a third day on Tuesday as 500,000 people fled the San Diego area, and firefighters made a desperate stand to save a mountain town ringed by flames.
More than a dozen fires blazed from the horse country north of Los Angeles to the Mexican border 240 km to the south, torching 1,500 houses and other buildings, blotting out the sun with smoke and raining ash on the streets.
Most of the destroyed homes were in the San Diego area, where three major wildfires burned unchecked and half a million people were ordered to leave in what may be the largest US evacuation since Hurricane Katrina hit the Gulf Coast in 2005.
At least five deaths were reported, three of them elderly evacuees from the San Diego area, and more than three dozen others had been injured, including 18 firefighters.
As the firestorms raged into the evening, Gov. Arnold Schwarzenegger asked President George W. Bush to upgrade California's wildfires to a "major disaster," which would trigger federal help.
Bush already issued a declaration of emergency early Tuesday. But Schwarzenegger told him in a new letter that "this disaster is of such severity and magnitude that effective response is beyond the capability of the state and local governments."
Schwarzenegger said 68,000 homes, from cabins to luxury villas, were threatened statewide and 6,000 men and women were working the fire lines. More than 300,000 acres have been blackened and the state government put economic losses in the hundreds of millions.
"We have had three things come together -- very dry areas, very hot weather and a lot of wind. This makes the perfect storm for fire," Schwarzenegger said at Lake Arrowhead, where blazes threatened two nearby mountain communities.
San Diego Mayor Jerry Sanders put the number of evacuees at half a million.
Bush planned to visit the fire-stricken area on Thursday.
Running Springs, a town of about 5,000 people nestled in the San Bernardino Mountains, was surrounded by fire by Tuesday afternoon as crews made a furious effort to save homes.
California power authorities issued a transmission emergency because downed power lines had left San Diego with only 60 percent of its usual supply of electricity.
The hot Santa Ana winds, which have fanned the flames as they blow in to Southern California from the desert, continued to gust up to 105 kmph and high wind warnings remained in effect for most of the region until Wednesday afternoon.
Officials were hoping that easing winds and an accompanying rise in humidity would help them gain the upper hand against the wildfires.