Aug. 5 (UPI) -- A wildfire that ignited Friday in Southern California has exploded to tens of thousands of acres as nearly 2,000 firefighters work to get the blaze under control.

The Gifford Fire, burning in San Luis Obispo and Santa Barbara counties, about 90 miles north of Los Angeles, has prompted officials to issue evacuation orders throughout both regions.

"Immediate threat to life. This is a lawful order to LEAVE NOW," Cal Fire said in an update, adding that several other areas, mostly in San Luis Obispo County, are under evacuation warnings.

Some 1,910 firefighters were on the ground, as the blaze threatened 872 structures, officials said.

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