iStock/Thinkstock(NEW YORK) -- California Gov. Jerry Brown declared a state of emergency for two counties near Los Angeles Thursday night, as the nearby Holy wildfire exploded in size.

The Holy Fire is just one of 13 large wildfires currently burning across California, five of which remain under 50 percent contained. Altogether, the various blazes have scorched more than 671,000 acres, destroyed or damaged over 2,000 structures and have forced thousands of residents from their homes.

The massive Holy fire, which ignited in Southern California's Cleveland National Forest Monday afternoon, has spread rapidly and nearing Orange and Riverside counties. The fast-moving fire had burned an area of more than 18,000 acres by Friday morning and was only 5 percent contained, officials said.

Throngs of firefighters are on the front lines battling the blaze, using fire engines, helicopters and bulldozers. Mandatory evacuations were still in effect for various communities Friday morning.

The official cause of the Holy Fire is still under investigation, but a man, Forrest Gordon Clark, is accused of setting the fire in Cleveland National Forest's Trabuco Canyon.

The Orange County Fire Authority arrested Clark on Wednesday on suspicion of felony arson. The 51-year-old Trabuco Canyon resident was scheduled to be arraigned Friday on the following charges: one felony count each of aggravated arson of five or more inhabited structures, arson of inhabited property, arson of forest, criminal threats; two felony counts of resisting and deterring an executive officer; and a sentencing enhancement for arson burning multiple structures.

Clark is being held on $1 million bail and faces a maximum sentence of life in state prison, according to the Orange County District Attorney's Office.

No major injuries linked to the Holy Fire have been reported, but the Carr Fire in Northern California has been blamed for the deaths of at least eight people, officials said.

The "mechanical failure of a vehicle" ignited the Carr Fire in Whiskeytown on July 23, according to the California Department of Forestry and Fire Protection. The flames ripped through northwest Shasta County then spread southeast for days, with little containment, as it swept across the Sacramento River and roared toward the city limits of Redding, which is home to 92,000 people.

By Friday morning, the blaze had burned an are of more than 181,000 acres in Shasta and Trinity counties. Some 1,600 homes, businesses and other structures have been destroyed by the Carr Fire, while hundreds of others have been damaged.

Gusty winds, high temperatures and dry vegetation have spurred fire growth. But thousands of firefighters who have been continuously battling the Carr Fire have made progress in recent days. The blaze was at a containment of 51 percent Friday morning, officials said.

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