Updated

At least 23 wildfires raged in forests and woodlands across California Sunday, taking the life of one firefighter and forcing hundreds to flee their homes.

The biggest California wildfire — raging in the Lower Lake area north of San Francisco — spread overnight to cover even more drought-stricken ground, expanding more than 30 square miles in four or five hours, said California's Forestry and Fire Protection Director Ken Pimlott.

The fast-moving blaze had charred 84 square miles by Sunday, an area much bigger than San Francisco's 49 square miles. It is only 5 percent contained.

The fire has destroyed 24 homes and 26 outbuildings and was threatening 6,300 homes. Cal Fire says an evacuation advisory has been issued affecting 12,000 people in a sweeping region of ranches and small rural communities. Several roads have been closed.

At least 650 residents have been evacuated from their homes as the blaze raged in hills covered in dense brush and oak trees and dotted with ranch homes.

"We saw it behind our house. We saw the smoke pouring over. So we just started collecting stuff and we left, to find out later that everyone was evacuated out here," said resident Julie Flannery. When her family returned Friday, they found their two horses and one mule were gone. They hoped firefighters turned them loose so they could make their way to safety.

"The rest of this is just material stuff," she said. "The animals and the family is the most important."

Approximately 9,000 firefighters were working across northern California to subdue the blazes, a task made, something made incredibly difficult by several years of drought that have dried out the state.

"The conditions and fire behavior we're seeing at 10 in the morning is typically what we'd see in late afternoon in late August and September," said Nick Schuler, a division chief with Cal Fire. "But because of the dry conditions, because of the drought-stricken vegetation accompanied by the steep terrain and winds, we're seeing fire activity that's abnormal for this time of year."

Many of the blazes were sparked by lightning and exacerbated by tinder-dry trees and grass, as well as erratic winds, Pimlott said.

"The biggest challenge is the extreme and explosive rates of spread of these fires," he said.

The fires forced Gov. Jerry Brown to declare a state of emergency for California and activate the California National Guard to help with disaster recovery.

California on Sunday secured a grant from the Federal Emergency Management Agency, or FEMA, to help ensure the availability of vital resources to suppress the blaze burning in Lake County, said California Governor's Office of Emergency Services Director Mark Ghilarducci.

The federal grant will assist local, state and tribal agencies responding to the fire to apply for 75 percent reimbursement of their eligible fire suppression costs, Ghilarducci said.

Earlier this week, Engine Capt. David Ruhl, from South Dakota, was killed battling a fast-moving blaze that broke out on Thursday in the Modoc National Forest, located about 100 miles south of Oregon.

Ruhl was in a vehicle Thursday, looking for ways to fight the blaze, when officials lost contact with him, fire information officer Ken Sandusky said. His body was recovered on Friday. An autopsy to determine the cause of death will be conducted this week, the U.S. Forest Service said.

Ruhl had been helping California firefighters since June. He was originally part of a Black Hills National Forest firefighting team. The Modoc fire had grown to about 6 acres by Sunday, and it was 20 percent contained.

In Humboldt County, 600 firefighters were battling 18 small blazes Sunday that were sparked by lightning. At least 70 fires have been reported in the area since Thursday. Of those, 52 have been contained, Cal Fire said.

The blazes have charred 1,200 acres and destroyed two structures in steep, difficult to access terrain.

Meanwhile, A woman was arrested in connection with a small fire near Goveland, a stop-off point headed to Yosemite National Park.

The 200-acre fire, about 20 miles from the park's entrance, was 80 percent contained Sunday. All evacuations were lifted Saturday and residents were allowed to return to their homes.

Lisa Ann Vilmur was arrested Thursday night on allegations of recklessly causing a fire. She was jailed on $100,000 bail, and it was not known if she has an attorney who could comment.

Three firefighters who were burned on a fire northeast of Sacramento on Saturday have been released from the hospital. One has returned to duty and all are expected to make a full recovery, fire officials said.

A fourth firefighter remains hospitalized with serious burns.

The fire that began on July 25 destroyed two buildings and 54 homes and other buildings are still considered at risk in Placer and Nevada Counties. The 3 1/2-square-mile blaze is 85 percent contained.

At least 200 homes were evacuated in a community of Cascadel Woods in central California. Authorities say a boy acknowledged starting the fire near Bass Lake by plying with a lighter to burn pine needles. The fire has grown to more than 6 square miles and is partially contained.

Crews battling a fire east of Napa Valley held their ground Saturday, more than a week after the blaze started about 45 miles east of Napa's wine county.

More than 12 square miles in Solano County have been charred, but the fire was 92 percent contained, and crews expected to have it fully corralled by Monday.

The Associated Press contributed to this report.