Firefighters are working to put out nine wildfires that were sparked by lightning in the northeastern corner of California as a stubborn blaze to the west in Mendocino County continues to challenge crews.

The new fires in Lassen, Modoc and Shasta counties were not threatening any structures, but CalFire says crews were trying to contain them so they can concentrate on the larger fire.

The bigger wildfire was sparked by lightning on July 30 and has burned 13.5 square miles of dry brush and timber near Laytonville in Mendocino County.

An evacuation order remains in effect as the fire about 160 miles north of San Francisco threatens nearly 60 structures across six communities.

More than 2,000 firefighters working in steep, rugged terrain have contained 35 percent of the blaze.

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