The fires have forced an estimated 500,000 people to leave their homes and scorched 172,000 hectares of countryside stretching from Malibu to beyond the Mexican border.
Death toll up
Arnold Schwarzenegger, the California governor, said that the fires are the worst to hit California since devastating the fires of 2003 which claimed 22 lives.
As night fell across the state, some 15 fires were still blazing largely out of control, mostly in San Diego county.
The county, at the southern end of California, has been hardest hit by the four days of intense fires, suffering losses in excess of $1bn, and three of the largest fires still burned out of control there.
|Thick smoke hangs over much|
of California's lower half [AFP]
But a drop in temperatures and weaker Santa Ana winds had slowed their march towards threatened communities.
Al Jazeera's Kelly Rockwell, reporting from southern California, said the disaster has been declared a federal emergency, meaning that local residents will receive federal assistance along with help from the state government.
State and local governments as well as the federal government and private companies are pitching in, she said.
Dulce Herrere and her family had gone through the same thing four years ago.
"We never thought it would happen again," she said.
Volunteers too are turning up in big numbers, Rockwell said.
Sharon Lawson, a Red Cross volunteer, said: "I was ready and on call and when they called, here I am."
As a volunteer for the Red Cross, Lawson is walking through neighbourhoods assessing the damage to homes, Rockwell said.
The Federal Emergency Management Agency (Fema) had 1,000 people on the ground in San Diego.
A San Diego local official inspects a burnt
home along Del Dios Highway [AFP]
Fema and Bush were both criticised for being slow to respond when Hurricane Katrina struck New Orleans and the Gulf Coast region in 2005.
Ken Higgingbothom, Fema head, said: "There are still fires burning at this time, and unfortunately there will probably be more damage, so do the math, it will probably go even higher."
Some of the fires remain at very low containment and round-the-clock crews have been brought in to fight them.
After the largest evacuation in California's modern history, some residents were allowed to go home.
One of the most desperate fights was in Orange county, south of Los Angeles, where the 20,000-acre Santiago fire threatened homes in a gated community.
Though weather conditions have been blamed for the spread of the fires, there is now a federal investigation into whether some of the fires are the work of arsonists, Rockwell reported.
Authorities said federal agents from the FBI and Bureau of Alcohol, Tobacco and Firearms joined local authorities in investigating the Santiago fire as an arson.
More than 500,000 people evacuated
More than 172,000 hectares of state's countryside scorched
More than 1,700 buildings destroyed and emergency declared in most of California
Three dead and another 40 injured, including firefighters
"Those are crime scenes," said Jim Amormino, spokesman for the Orange county sheriff's department.
He said a $70,000 reward has been posted for information leading to the arrest and conviction of those responsible.
A shift in the wind, from hot dry Santa Ana gusts blowing in from the deserts to an onshore flow of cooler, more moist air coming from the Pacific, helped firefighters hold the line of the flames, which began moving away from populated areas.
Los Angeles county also reported progress, cancelling wind warnings for the first time since the weekend.
Top wind speeds fell to below 80kph after gale force gusts hit 130kph.
San Diego county officials said that even when the fires were extinguished they would face a major clean-up and huge costs.
|A blazing hillside is seen from the entrance of Camp Pendleton on Wednesday [AFP]|