Most of the dead ignored earlier calls to evacuate their homes, officials said on Tuesday.
US President George Bush on Monday declared a major disaster in southern California, which is being hit by its worst fires since 1991.
More than 11,000 firefighters, including emergency back-up from the nearby states of Nevada and Arizona, are battling the flames that have already created the biggest fire disaster in Californian history.
"It's a rolling disaster that's just growing in size; it's overwhelming," said Patty Roberts of the Office of Emergency Services (OES), which is co-ordinating fire data.
"We are battling on all fronts," she said. "On the one hand, we're trying to deal with the rolling fire disasters and on the other we are trying to help the victims that they have already hurt."
Owing to the fluidity of the situation, no estimates of the damage and cost of fighting the fires could immediately be obtained. But media estimates have run anywhere from $500 million to three billion.
A firefighter walks past a wall of
flames in San Bernadino
At least 114,800 hectares have been burned around the southern city of San Diego, which was almost completely surrounded by three major fires.
Another blaze in the Los Angeles area was covering around 38,000 hectares on Tuesday, with firefighters and aircraft desperately trying to keep the flames from hundreds of luxury homes threatened in the plush area.
Some 16 houses have already been destroyed in that blaze and a further eight damaged, fire department officials said.
The region's third major blaze entered its eighth day in San Bernardino County, about 80km east of Los Angeles, with at least 33,292 hectares burned.
Authorities suspect arson as the cause of at least two of the fires.
Countless people from the stricken areas were forced to flee their homes and stay with relatives or in Red Cross shelters.
US Forestry Service officials in San Bernardino County estimate that around 40,000 people have fled their homes.
The scope and scale of the fires resulted in a health warning from the American Lung Association of San Diego.
"The particulate-matter pollution is at least twice the level of the federal maximum," said Ross Porter, communications director for the American Lung Association of San Diego.
"The air is unhealthy and likely to remain so," he said.
Most at risk are children, seniors, pregnant women and people who suffer from heart disease or lung disease.
Officials say the fires have
resulted in rising pollution levels
Residents should try to minimise their exposure to the smoke and ash by staying indoors, shutting windows or going somewhere with air conditioning, Porter said.
Ash and thick smoke rained down on large swathes of Los Angeles, which was also hemmed in by flames as another giant blaze raged in San Bernardino County, 80km east of the city.
Even Hollywood has been affected by the monstrous fire storms.
The set of a new film starring Leonardo DiCaprio was partially destroyed by a fire roaring through the Simi Valley, northeast of Los Angeles, Daily Variety said.
Film studios Warner Brothers and Miramax Pictures had to cancel plans to shoot flying scenes on a farm in the area.
Producers shifted production to the port city of Long Beach, south of Los Angeles, where they switched to interior shooting as the skies of Los Angeles were blanketed by a pall of thick smoke.