SANTA ROSA (CBS SF) — The death toll from out-of-control Northern California wine country wildfires rose to 31 Thursday, while breached fire lines prompted new evacuations.

With word of additional fatalities in Sonoma and Mendocino counties, the wildfires together are now the deadliest in California history. While the Oakland Hills fire of 1991 killed 25 people by itself and the Griffith Park fire in Los Angeles in 1933 killed 29, never in recorded state history have so many people been killed by a simultaneous series of fires, said Daniel Berlant, a deputy director with the California Department of Forestry and Fire Protection.

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Hundreds are still listed as missing and officials fear the death toll may surge.

Sonoma County Sheriff Robert Giordano said most of the bodies were found during targeted searches. “Because people either called and gave us enough information that we felt we needed to go look for them, or they called to report them missing and we tracked the circumstances backwards enough to where we realized we now had to go look for them.”

Giordano said 400 people were still listed as missing. Recovery crews using cadaver dogs were allowing burn areas to cool Thursday as they searched for victims.

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Most of those found dead in the county were elderly found inside their homes. “The youngest person on this list is 57 years old,” said Giordano. “The bulk of them are in their 70s and 80s.”

Firefighters look for hotspots in the destroyed Coffey Park neighborhood in Santa Rosa, California, October 12, 2017. (ROBYN BECK/AFP/Getty Images)

Earlier Thursday, Giordano said identifying the bodies was also proving to be a challenge because of the condition of the remains.

Major Northern California Wildfires (Source: Cal Fire)
As of 6:30 p.m. PT

Cherokee Fire – 8,360 acres, 65% contained – Off Cherokee Road and Zonalea Lane, Oroville
La Porte Fire – 6,109 acres, 25% contained – La Porte Rd. and Oro Bangor Hwy, Bangor

Sulphur Fire – 2,500 acres, 55% contained – Off Hwy 20, Sulphur Bank Road, Clearlake Oaks

Redwood/Potter Fires – 32,100 acres, 5% contained – N of Hwy 20, W of Mendocino Nat’l Forest

Partrick Fire – 10,817 acres, 3% contained – Off Partrick Road, W of Napa
Tubbs Fire – 34,770 acres, 10% contained – Off Hwy 128 and Bennett Ln, Calistoga

Atlas Fire – 43,762 acres, 7% contained – Off Atlas Peak Rd, south of Lake Berryessa

37 Fire – 1,660 acres, 90% contained – Hwy 37 & Lakeville Highway
Adobe Fire – 7,900 acres, 1% contained – Near Kenwood
Nuns/Norrbom Fires – 17,798 acres, 3% contained – Hwy 12, N of Glen Ellen
Pocket Fire – 8,430 acres, 0% contained – Off Pocket Ranch Rd and Ridge Ranch Rd, Geyserville
Pressley Fire – 473 acres, 1% contained – East of Rohnert Park

Cascade Fire – 10,200 acres, 45% contained – Cascade Wy & Marysville Rd, N of Collins Lake

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In Mendocino County, a number of areas remained under mandatory evacuation orders because of the merged Redwood and Potter Fires,  part of the Mendocino Lake Complex Fire which also includes the Sulphur Fire.

Mendocino County Sheriff Tom Allman said Thursday afternoon the expects the number of deaths in the county to go up from the current eight victims.

Mendocino County has the second highest fire death toll behind Sonoma County (17). Four people have been found dead in Yuba County and two in Napa County.

All of the deaths in Mendocino County were attributed to the Redwood Fire and came on first night of the fire, he said.

The fire is now at 32,100 acres and 5 percent contained. An estimated 5,000 people have been displaced in evacuations.

In Napa County Thursday, the Tubbs Fire continued its advance from Sonoma County and jumped Highway 29 northeast of the town of Calistoga. The blaze had consumed at least 34,000 acres and was 10 percent contained.

Calistoga, the historic resort town of wine tastings and hot springs with 5,300 residents, has been evacuated and sheriff’s deputies were patrolling the streets early Thursday protecting the abandoned homes and businesses from looters.

To the southeast, another battle was being waged against the massive Atlas Fire, The blaze was the largest of the wine county wildfires having consumed 43,700 acres and was just 3 percent contained.

So far, the Atlas Fire has left devastation across Napa County — destroying wineries, houses, businesses and driving thousands from their homes — and now has marched into neighboring Solano County, where another 2,500 people have been evacuated.

The front lines Thursday were near just east of Highway 221 — the Napa-Vallejo Highway — where the Atlas Fire was burning its way through the Skyline Wilderness Park. While no structures were threatened, there was plenty of fuel in the form of grass and brush to allow the blaze to pick up momentum.

The worry was the shifting winds would drive it back into Napa County toward areas that have been so far untouched by the wildfire outbreak.

Also in Sonoma County, the Nuns and Norrborn fires were burning on each side of the city of Sonoma, having merged together overnight. Together they have burned nearly 15,000 acres with only three percent containment.

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The community of Boyes Hot Springs in Sonoma County was also told to clear out Wednesday and the streets were quickly lined with cars packed with people fleeing.

“That’s very bad,” resident Nick Hinman said when a deputy sheriff warned him that the driving winds could shift the wildfires toward the town of Sonoma proper, where 11,000 people live. “It’ll go up like a candle.”

The 22 fires in wine country spanned more than 265 square miles as they entered their fifth day, many of them completely out of control. Modern, strategic attacks that have kept destruction and death tolls low in recent years just haven’t worked against their ferocity.

“We are literally looking at explosive vegetation,” Cal Fire Director Ken Pimlott said. “Make no mistake,” he later added, “this is a serious, critical, catastrophic event.”

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Air quality was also an issue as far away as San Jose as smoke from the blazes choked the Bay Area. Dozens of school districts and colleges across the region have cancelled classes for the remainder of the week because of the unhealthy air.