LAKE COUNTY (CBS/CBSSF/AP) — More than 12,000 firefighters are battling 17 wildfires across California.

Saturday afternoon, a new fire erupted into a wall of flames in Lake County.

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It has been dubbed the Peterson Fire, and is the third fire to hit the county this summer. How it started is unknown.

The blaze erupted shortly before 5:30 p.m., and spread to 400 acres in just 2 hours.

Cal Fire has over 200 firefighters battling the flames. Helicopters and air tankers have been called in.

So far no evacuations have been ordered and no homes or buildings have been damaged.

Meanwhile, the Jerusalem Fire in Lake and Napa counties is 25,118 acres and 98% contained, according to information released by Cal Fire Saturday morning.

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So far, the fire has destroyed six residences and 21 outbuildings.

All evacuations and road closures have been lifted.

The cause of the fire remains under investigation.

Three hundred and eighty-two firefighters, 13 fire engines, seven fire crews, a helicopter, 12 bulldozers and nine water tenders have been dispatched to help battle the blaze since it started on Aug. 9.

Another fire that has burned for nearly three weeks on the western slope of the Sierra Nevada grew to 73 square miles near Kings Canyon National Park and was bearing down on popular Hume Lake.

The blaze on Friday burned down Kings Canyon lodge that had been evacuated earlier in the week, the first structure it had claimed since lightning sparked it three weeks ago. Pieces of foundation, charred metal pipes and a burned-out truck were all that remained. No injuries were reported.

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More than 2,500 campers, hikers, employees and residents have been evacuated this week.

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