At least 14 wildfires have scorched about 425 square miles from north of Los Angeles to southeast of San Diego.
San Diego officials said the damage could be worse than the destruction caused four years ago by similar fires, which cost $1.1 billion and damaged 4,847 structures.
National Guard troops were posted at Qualcomm Stadium, home to the NFL's San Diego Chargers, as it became a temporary home to 10,000 fire evacuees.
President Bush issued an emergency declaration Tuesday for seven California counties, clearing the way for federal disaster relief. Bush's declaration covers the same seven counties that Gov. Arnold Schwarzenegger declared as in a state of emergency Monday: Los Angeles, Orange, Riverside, San Bernardino, San Diego, Santa Barbara and Ventura.
"This is nowhere near finished,'' said Chief Bill Metcalf, San Diego County area fire coordinator. "It is worse than many of us imagined. We're seeing 100- to 200-feet flame lengths and truly explosive fire behavior.''
The fires also destroyed buildings in Malibu, where many movie stars have homes northwest of Los Angeles, and Lake Arrowhead, a mountain community northeast of Los Angeles. Roads and freeways near the affected areas were closed because of the fires or jammed with people fleeing.
“It's a tragic time for California,'' Schwarzenegger said after touring the affected areas. "The conditions are really terrible.''