The Hollywood Hills has blazed uncontrollably as the worst wildfires in the history of Los Angeles raged across the city and deep into the storied heartland of the American film industry.
A crescent of flame on Thursday morning squeezed Los Angeles in a huge pincer visible from space.
More than 100,000 people were ordered to leave as dry, hurricane-force winds hindered firefighting operations and spread the flames.
At least five people have been killed since the fires erupted on Tuesday.
The homes of movie stars and celebrities were among those consumed by flames, which tore through some of the world's most lavish real estate and above showbiz landmarks instantly recognisable around the world.
"This firestorm is the big one," Los Angeles Mayor Karen Bass told a news conference after rushing back to the city, cutting short an official trip to Ghana.
At least six separate wildfires were burning in Los Angeles County.
Three of them were totally out of control, including a pair of huge conflagrations on the city's eastern and western flanks and the smaller Sunset Fire raging in Hollywood Hills just above Hollywood Boulevard and its Walk of Fame.
The LA Fire Department issued an evacuation order for people in an area within Hollywood Boulevard to the south, Mulholland Drive to the north, the 101 Freeway to the east and Laurel Canyon Boulevard to the west - all iconic addresses for film, TV and music.
The Hollywood Sign is across the freeway.
On the west side of Los Angeles, the Palisades Fire consumed more than 6400 hectares and hundreds of structures in the hills between Santa Monica and Malibu, racing down Topanga Canyon until reaching the Pacific Ocean on Tuesday.
Celebrities have shared their heartbreak on social media and described the devastation as they joined the thousands ordered to evacuate.
Film star Billy Crystal and his wife Janice lost their home of 46 years, while media personality Paris Hilton described watching her beachfront house in Malibu "burn to the ground on live TV".
Thousands of Los Angelenos fleeing the flames sought refuge in temporary shelters.
Aerial video by KTLA television showed block after block of smouldering homes in Pacific Palisades, the smoky grid occasionally punctuated by the orange blaze of another home still on fire.
To the east, in the foothills of the San Gabriel Mountains, the Eaton Fire claimed another 4289ha, another 1000 structures, and killed at least five people, officials said.
"We're facing a historic natural disaster. And I think that can't be stated strong enough," Kevin McGowan, director of emergency management for Los Angeles County, told a press conference.
Even though forecasters said winds would subside briefly on Wednesday night, so-called red flag conditions were expected to remain until Friday.
Large animals found shelter from the wildfires at a college equestrian centre that opened its doors to horses, alpacas, llamas and even pigs.
Nearly 300,000 homes and businesses were without power in Los Angeles County, down from nearly one million earlier on Wednesday, according to PowerOutage.us.
School was cancelled throughout Los Angeles County at least through Thursday.
The scale and spread of the blazes stretched exhausted firefighting crews beyond their capacity.
Firefighters from six other US states were being rushed to California, while an additional 250 engine companies with 1,000 personnel were being moved from Northern California to Southern California, Los Angeles County Fire Chief Anthony Marrone told a news conference.
Water shortages caused some hydrants to run dry in upscale Pacific Palisades, officials said.
"We pushed the system to the extreme. We're fighting a wildfire with urban water systems," Janisse Quinones, chief executive of the Los Angeles Department of Water and Power, told reporters.
The fires struck at an especially vulnerable time for southern California, which has not seen significant rainfall for months.
Then came the powerful Santa Ana winds, bringing dry desert air from the east toward the coastal mountains, fanning wildfires while blowing over the hilltops and down through the canyons.
