Thousands of Southern California homes could be at risk in coming days as powerful Santa Ana winds continue to stoke wildfires, fire officials said. Blazes on Sunday scorched thousands of acres from the Mexican border to Santa Barbara County, destroyed at least 39 homes and other buildings and killed at least one person.

Some of the worst devastation has been in and around Malibu, where the losses included two beloved landmarks; in San Diego, where at least one person died and 14 were injured; and in the communities of Agua Dulce and Canyon Country, midway between Santa Clarita and Palmdale. At least 25 buildings there were destroyed and 3,800 remained threatened by a rapidly moving blaze driven by winds gusting to 80 mph. At least four people were reported injured, one severely.

In Orange County, a late-developing fire that broke out in the area of Silverado Canyon and Santiago Canyon roads quickly swelled Sunday evening and moved toward the Portola Springs and Northwood communities. At 11 p.m., fire officials said they were asking residents to evacuate two of the most endangered neighborhoods.

Orange County Fire Authority Capt. Stephen Miller said winds were blowing between 35 and 45 mph and firefighters were making a stand between homes and the blaze. "The biggest problem besides the winds is the tremendous amount of people congesting the highways to watch," he said.

In all, more than a dozen fires raged across the region, forcing thousands of residents to evacuate their homes. At least five firefighters were injured. Gov. Arnold Schwarzenegger declared a state of emergency in the affected areas.

It was not clear what caused most of the fires, but officials said downed power lines might be to blame for the Malibu and Agua Dulce blazes.

The Malibu fire, which had burned more than 2,200 acres, receded Sunday evening as winds died down there, but fire officials warned that it remained uncontained. "This fire is not over," Los Angeles County Fire Chief Michael Freeman said in a briefing at a command center in Malibu. "We're a long way from there at this point." Firefighters probably would not be able to contain the fire before Tuesday or Wednesday, he said.

The fires around the region were stoked by Santa Ana winds that peaked at hurricane strength. They were fueled by brush and timber that flourished during the wet winter of 2004-05 then was seared by a record drought over the last year.

"This was a conflagration that we knew was coming at some point," Los Angeles County Supervisor Zev Yaroslavsky said. "We were cruising for a bruising."

The National Weather Service issued a high-wind warning through Tuesday afternoon, and forecasters warned that wind speeds today could surpass those of Sunday. Los Angeles County Sheriff Lee Baca estimated that the fires would last five days.

The South Coast Air Quality District issued a warning that air quality in portions of Los Angeles County could reach unhealthful levels because of the fires and urged residents to avoid unnecessary outdoor activities in smoky areas.

Roughly 1,400 firefighters from throughout California were battling the Malibu blaze.

"We are at the mercy of the wind," said Malibu Mayor Pamela Conley Ulich after the firestorm had blown down through canyons and into the center of the seaside community, which is nearly as famous for its periodic disasters as it is for its $60-million homes, billionaire residents and priceless ocean views. Malibu last suffered devastating fires in 1993 and 1996.

Among the losses this time were Castle Kashan, an ornate, 10,000-square-foot hillside home that loomed over Malibu Lagoon, and Malibu Presbyterian Church.

Some Malibu residents spent the night at Red Cross shelters in Agoura Hills or Pacific Palisades. Authorities closed Pacific Coast Highway and other major thoroughfares, while officials canceled classes today at Pepperdine University and six schools in the Malibu area.

The Agua Dulce blaze, dubbed the Buckweed fire, began shortly before 1 p.m. Sunday and grew in just a few hours into a dynamo that had charred roughly 12,500 acres. The fire moved so rapidly that firefighters had to move their command center five times, retreating gradually to Santa Clarita.

In San Diego, the fires drew immediate comparison to the devastating wildfires of October 2003. The Witch Creek Fire in northeastern San Diego County burned much the same terrain as the 2003 Cedar Fire, which burned for 10 days and claimed 15 lives. The larger Harris fire, along the U.S.-Mexico border, resulted in the only death reported in Sunday's blazes, a man believed to be an illegal immigrant seeking to cross the border. The fire also left four firefighters and at least 14 civilians injured, including a 15-year-old boy burned over 70% of his body. One home burned.

The fire spread through an area that is a common path for migrants from Mexico, and authorities feared the death and injury toll would rise.

The Malibu fire began shortly before 5 a.m. Sunday, four miles up Malibu Canyon from the Pacific Ocean, then sprinted south down the canyon toward the coast and the hilltop campus of Pepperdine University.