Updated

Even as many of the wildfires in flame-ravaged Southern California died down and residents returned home, lingering dust and soot-laden air made it difficult for many to breathe even a sigh of relief Saturday.

Air quality remained poor in the central San Bernardino Mountains and parts of the San Bernardino Valley, as well as swaths of Orange and Riverside Counties. In San Diego County, where only two of five major fires were more than 50 percent contained, the air was especially dismal Friday.

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Joe Flynn, 48, worried about air quality as he prepared to return home to Ramona, northeast of San Diego, after a stay at Qualcomm Stadium, where thousands of evacuees sought shelter this week. But the pull to get back to normal was even stronger.

"Sure I'm worried about breathing that stuff up there," he said. "It's not cool, but everyone is dying to get back home."

Satellite pictures continued to show a thick haze of smoke hanging over the entire region, affecting schools, events and the health of residents all over Southern California.

Residents staying in areas with bad air were advised to avoid exerting themselves. Children and those with heart and respiratory conditions were urged to stay indoors with the windows and doors closed and the air conditioner on.

"In the immediate aftermath of a fire, we're all at risk of the fine particulate matter we can inhale," said Julia Robinson Shimizu, a spokeswoman for Breathe L.A. "In general it's good to limit outdoor strenuous activity at least seven days after the fires have ended."

In San Diego, the University of California San Diego Medical Center saw an increase in patients coming in with breathing troubles they believe were related to air pollution, spokeswoman Jackie Carr said.

Mayor Jerry Sanders said the San Diego Chargers would play Sunday's game scheduled at Qualcomm. The stadium can seat more than 70,000 fans.

But Ross Porter, a spokesman for the American Lung Association of California, urged fans to use caution when deciding whether to attend.

"Sometimes its better to sit quietly at home and watch it on TV," he said.

Meanwhile, about 23,000 homes were still endangered by five major blazes in three counties. Altogether, more than a dozen fires raced across more than 503,000 acres — the equivalent of 786 square miles (2036 square kilometers) — although many of the blazes have been contained.

At least three people — and possibly as many as seven — have been killed by flames. About 1,700 homes have been destroyed and damage estimates have surpassed US$1 billion.

On Friday, tens of thousands of displaced families began returning to their fire-ravaged communities, but it will likely be months or even years before they recover the comforts they left behind when they fled giant walls of flames.

Gov. Arnold Schwarzenegger's office said he would appear Saturday morning at an Orange County fire command post to discuss efforts to find arsonists, as well as to warn about charlatans peddling insurance scams to fire victims.

On Friday, the governor signed an executive order he said would cut red tape by directing state agencies to aid fire victims with such things as filing for tax extensions and unemployment insurance.

On the other side of the Cleveland National Forest, residents in the Riverside County town of Corona worried that flames they had watched on the news all week might reach them. They packed an elementary school Friday and heard assurances that there was no imminent threat, though some packed valuables in their cars, just in case.

"Your feelings are real but we want to relieve some of that anxiety," John Hawkins, Riverside County fire chief, told residents.

Also Friday, Sen. Dianne Feinstein urged Congressional leaders to provide an additional US$1 billion for firefighting and fire recovery efforts.

The National Weather Service had some good news for firefighters: Winds were forecast to be light on Saturday, with highs hovering around 80 in most of the active fire areas.