US President Donald Trump has declared a state of emergency in southern California, where wildfires have forced more than 200,000 people to flee their homes.
The fires have been roaring through canyons, hillsides and densely populated areas, including wealthy Bel Air, for four days.
Hundreds of homes have been destroyed and many schools in Los Angeles are closed.
Authorities fear that four major fires – ranging from LA up the Pacific coast to Santa Barbara County – may be whipped up by the region’s notorious westward Santa Ana winds, which can reach hurricane strength.
The winds, which blow in hot and dry from the California desert, could reach 75mph and create “extreme fire danger”, according to an alert from the countywide emergency system in Los Angeles.
The National Weather Service said high winds were not expected to die down until at least the end of Saturday.
The state of emergency frees up federal aid and kick-starts a chain of disaster relief efforts in the counties of Los Angeles, Riverside, San Diego, Santa Barbara and Ventura.
No civilian casualties or deaths have been reported, but three firefighters have been injured, the Los Angeles Fire Department said.
The Los Angeles Unified School District, the country’s second largest with more than 640,000 students, said it closed at least 265 of almost 1,100 schools.
Dozens of schools have also been closed in neighbouring Ventura County, where the Thomas fire, the largest of the blazes, has charred more than 96,000 acres.
The fires have created apocalyptic scenes of flaming mountains and walls of smoke, with firefighters spraying water and helicopters dumping bucket-loads in attempts to contain the flames.
Jake Sandell, a resident in Santa Paula in Ventura County, said: “You don’t expect things like this.
“I was expecting this year to see snow on that mountain and now the thing is on fire.”
Because of the heavy smoke, the South Coast Air Quality Management District has warned residents, especially the elderly, children, pregnant women and people with respiratory diseases, to stay indoors.
In the San Fernando Valley north of LA, the Creek fire has destroyed at least 30 homes, blackened more than 12,000 acres and forced the evacuation of 2,500 homes and a health centre.
Another blaze, the Rye fire, threatened more than 5,000 homes and structures northwest of Los Angeles.
(c) Sky News 2017: State of emergency declared over southern California wildfires