President Bush has promised federal aid for Californians whose homes have been destroyed by at least 16 wildfires raging in the southern part of the state. The blazes have scorched 165,000 hectares. In San Diego, where 1,200 homes were destroyed, local officials say losses could total $1 billion. Mike O'Sullivan has more from Los Angeles.

With at least half a million people forced from their homes, President Bush signed a major disaster declaration, allowing federal officials to make grants for temporary housing and home repairs, and providing low-cost loans to property owners whose losses are not covered by insurance.

State and local firefighters are already getting aid from the federal government, including fire crews, helicopters, and air tankers that carry water and fire retardant chemicals. The Department of Defense has supplied six C-130 aircraft equipped with firefighting systems, and National Guard troops are helping with evacuation and crowd control.

President Bush plans to visit the fire-ravaged parts of the state Thursday, and says he is making sure that federal efforts are coordinated. He also told fire victims that people across the country care deeply about them.

"We are concerned about their safety. We are concerned about their property. And we offer our prayers and hopes that all will turn out fine in the end. In the meantime, they can rest assured that the federal government will do everything we can to help put out these fires," he said.

Many of the hundreds of thousands of people forced from their homes have taken refuge in schools and community centers, in San Diego's Qualcomm sports stadium and at the Del Mar race track outside the city

Federal authorities were criticized for their response to Hurricane Katrina, which devastated New Orleans in 2005. Homeland Security Secretary Michael Chertoff, who toured the fire-stricken areas Tuesday, said lessons from Katrina are being applied to the fires.

As firefighters battle flames on the ground, air tankers and helicopters are dropping water and chemicals where the winds are low enough to permit it.

But airborne efforts have been hampered by high, gusty desert winds called Santa Anas. Forecasters expect the winds to diminish by Thursday, and offshore breezes, expected later in the week, should cool down temperatures, helping firefighters to make progress.