Some 27,000 residents were forced to flee their homes in the middle of the night as a fast-moving wildfire ripped through southern California.
Several thousand homes are under mandatory evacuation in the cities of Ventura and Santa Paula, some 70 miles (115 km) north of Los Angeles.
Firefighters warned the fire was moving so fast they were unable to contain it.
Fanned by high winds, the fire swept through tens of thousands of acres in a matter of hours.
It was earlier reported that one person died in a traffic accident while trying to flee the blaze, but Ventura County Fire Capt Steve Kaufmann has since told the Associated Press that no body was found in an overturned car.
Officials said one firefighter was injured. They also said 150 structures had been destroyed, and more than 260,000 people were without power.
A mental hospital and block of flats are reported to be among the buildings that have burned down.
Strong winds for days
Hundreds of firefighters worked through the night to tackle the blaze, named the Thomas Fire, but fire chiefs admitted they were fighting a losing battle.
“The prospects for containment are not good. Really, Mother Nature is going to decide,” Ventura County Fire Chief Mark Lorenzen earlier told reporters.
More than 1,000 firefighters are now battling the fires, which have burned 45,500 acres. Authorities have warned of widespread smoke and advised people with health conditions, the elderly and children to stay indoors in affected areas.
Forecasters say ferocious Santa Ana winds and low humidity will continue for a few days, making for extremely dangerous conditions.
#ThomasFire : updated acreage is 45,500 with zero containment. 1000+ firefighters still battling the blaze. Erratic winds and fire behavior is expected throughout the day.
— VCFD PIO (@VCFD_PIO) December 5, 2017