The Hollywood Hills blazed uncontrollably on Thursday morning 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 squeezed Los Angeles in a huge pincer visible from space. More than 100,000 people were ordered to evacuate 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 press 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 15,832 acres (6,406 hectares) and hundreds of structures in the hills between Santa Monica and Malibu, racing down Topanga Canyon until reaching the Pacific Ocean on Tuesday.

“We are heartbroken of course, but with the love of children and friends we will get through this,” said film star Billy Crystal and his wife Janice, announcing the Pacific Palisades home where they had lived since 1979 had been destroyed.

A wildfire ripped through an upscale coastal area of Los Angeles overnight, with Hollywood celebrities among those evacuating by car and on foot.

A wildfire ripped through an upscale coastal area of Los Angeles overnight, with Hollywood celebrities among those evacuating by car and on foot.

Media personality Paris Hilton said she was “heartbroken beyond words” after watching her beachfront house in Malibu “burn to the ground on live TV”.

Oscar winner Jamie Lee Curtis posted on Instagram: “My community and possibly my home is on fire.... Pray if you believe in it and even if you don't, pray for those who do.”

Thousands of Los Angelenos fleeing the flames sought refuge in temporary shelters.

Foad Farid found refuge in the gym of the Westwood Recreation Center with nothing but his car and his phone. Neighbours dropped off blankets, clothing, water, pizza and pet food. Jeff Harris arrived towing his Feisty Fish Poke food truck and began serving meals. “I’m just here to help,” he said.

Kevin Williams, at an evacuation centre in Pasadena, said he knew it was time to run when gas canisters at his neighbours’ homes began exploding under the heat.

“The wind whipped up, the flames were up about 30 or 40 feet high, and you hear 'pop, pop, pop'. It sounded like a war zone.”

Smouldering Ruins

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 10,600 acres (4,289 hectares), another 1,000 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.

“I think they sense the fire and so I really had to lead them in a way that they understood that they were being taken somewhere safe,” said Jaye Riedinger, 37, a creative director from Topanga, who left her home with her mustang horses.

Nearly 300,000 homes and businesses were without power in Los Angeles County, down from nearly 1 million earlier on Wednesday, according to PowerOutage.us. School was canceled throughout Los Angeles County at least through Thursday.

Water Woes

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 press 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.