Officials are making grim discoveries -- bodies burnt beyond recognition -- as they search the blackened ruins left by wildfires scorching parts of Northern California.
"Some of them are merely ashes and bones," Sonoma County Sheriff Rob Giordano said at a Thursday press conference. "And we may never get truly confirmative identification on ashes. When you're cremated, you can't get an ID."
Thirty-one people have been killed since the wildfires began Sunday night, making this outbreak one of the deadliest in state history, according to the California Department of Forestry and Fire Protection.
In Sonoma County, authorities had to turn to dental records, fingerprints, tattoos and serial numbers on hip implants to identify victims.
"We've been forced to work that direction because we may not have enough information to identify people, because of the fire and the severity of the burn," Giordano said.
Since Sunday, the deadly fires have leveled communities and thousands of homes, forced evacuations and produced unhealthy air quality in the San Francisco Bay Area.
"We're not even close to being out of this emergency," Mark Ghilarducci, the director of California's Office of Emergency Services, said Thursday afternoon.
The biggest fires in Northern California were far from contained.
The 43,000-plus acre Atlas fire in Napa and Solano counties was 7% contained, and the 34,000-acre Tubbs fire in Napa and Sonoma counties was 10% under control. The 32,000-acre Mendocino-Lake Complex fire was 10% contained.
• Seventeen of the 31 fire deaths were in Sonoma County, officials said. Eight people have died in Mendocino County, and at least four in Yuba County and two in Napa County, officials said.
• More than 2,800 residences in Santa Rosa have been destroyed by wildfires, Mayor Chris Coursey told reporters Thursday.
• Wildfires have burned more than 191,000 acres throughout California.
• Winds could be especially gusty Friday night through Saturday as new warnings were issued for the weekend, according to the National Weather Service. No rain is expected for almost a week.
How to help the victims of the California wildfires
• Almost 8,000 firefighters are trying to contain the blazes, officials said Thursday. They're using 820 firetrucks -- at least 170 from out of state -- 73 helicopters and more than 30 planes.
Many of the fire victims are elderly
At least 400 people are reported missing in Sonoma County alone, where a fire wiped out thousands of homes in Santa Rosa, a city of about 175,000 people.
Deputies are having to wait for houses to cool before they can enter to look for the missing, said Giordano, the sheriff.
The Sonoma County Sheriff's Office identified 10 victims Thursday,and most of them were over 70. The youngest was 57, and the oldest was 95.
Sonoma, Mendocino and Napa counties have been among the hardest hit by the fires. Nearly 20% of the population in those counties is over 65, according to US Census Bureau data.
Pregnant woman flees on bike
Evacuees who escaped the oncoming flames described harrowing ordeals.
Charity Ruiz, who is pregnant, had been in a car with her family trying to evacuate from their Santa Rosa neighborhood but got stuck in a traffic jam.
"Honestly, I've never in my life felt like I was going to die like that moment," Ruiz told CNN affiliate KPIX."Not just me, but my girls and unborn baby."
Unable to wait any longer, Ruiz walked back and got her bike from her house and rode out of the neighborhood with her two girls in the toddler trailer.
"I can ride a bike, but I'm pregnant so it was hard," she told the station. Ruiz had been scheduled to deliver her baby next week.
She and her kids made it out of harm's way, but their home burned to the ground.
'Peanuts' creator's home lost to wildfire
The fires have been fast and ruthless, shifting without much notice and destroying at least 3,500 structures.
One of them is the Santa Rosa home of Charles Schulz, the creator of the comic strip "Peanuts." Schulz died in 2000.
His widow, Jean, 78, evacuated from the home Monday, shortly before the flames reduced it to rubble, his son Monte Schulz said. The fire destroyed precious reminders of the life his stepmother and his late father had built together, along with memorabilia, Schulz told CNN.
Sleep-deprived firefighters are workingto contain the wildfires, even as some of their own homes have been hit.
Many have been working for days with little sleep -- but supervisors are trying to pull them off duty to get rest as firefighters from out of state arrive.
"We are finding people on the line that have just been going to work and staying out there for day after day after day," Napa County Fire Chief Barry Biermann said Thursday. "We're identifying them. We're getting them in as soon as we can to get rest, especially now that we have more reinforcements coming."
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