Wildfires menacing Los Angeles have killed at least 10 people and devoured nearly 10,000 structures, with five fires burning into a third night on Thursday as dry desert winds fanning the flames again gathered strength, according to China Daily.

The Palisades Fire between Santa Monica and Malibu on the city's western flank and the Eaton Fire in the east near Pasadena already rank as the most destructive in Los Angeles history, consuming more than 34,000 acres (13,750 hectares) - or some 53 square miles - turning entire neighborhoods to ash.

The death toll from the blazes rose to 10, Los Angeles county's Medical Examiner said in an update late on Thursday, without providing identities or other details.

Los Angeles County Sheriff Robert Luna told an earlier press conference he expected the number to grow.

"It looks like an atomic bomb dropped in these areas. I don't expect good news, and we're not looking forward to those numbers," Luna said.

Private forecaster AccuWeather estimated the damage and economic loss at $135 billion to $150 billion, portending an arduous recovery and soaring homeowners' insurance costs.

"We're already looking ahead to aggressively rebuild the city of Los Angeles," said Mayor Karen Bass, a Democrat, who faced criticism from President-elect Donald Trump and other Republicans over her handling of the disaster.

President Joe Biden, who declared a major disaster on Tuesday, promised on Thursday that the federal government would reimburse 100 percent of the recovery for the next 180 days to pay for debris and hazard material removal, temporary shelters and first responder salaries.

"I told the governor, local officials, spare no expense to do what they need to do and contain these fires," Biden said after meeting with senior advisers at the White House.

In all, five wildfires burned in Los Angeles county, with the largest Palisades fire just 6 percent contained and the Eaton fire 0 percent contained. Skies buzzed with aircraft dropping retardant and water on the flaming hills.

A large Super Scooper aircraft on loan from Canada was damaged and grounded after hitting an unauthorized civilian drone near the Palisades fire, the LA County Fire Department said. There were no injuries.

One rapidly growing blaze broke out on Thursday near Calabasas, one of the wealthiest cities in the US and home to numerous celebrities and gated communities. The so-called Kenneth Fire expanded to 960 acres (388 hectares) in a matter of hours.

With nerves on edge, Los Angeles county mistakenly sent an evacuation notice countywide to a population of 9.6 million, even though it had been meant only for the area of the Kenneth Fire, officials said. A correction was quickly sent.

Officials said the Eaton Fire had damaged or destroyed 4,000 to 5,000 structures while the Palisades Fire destroyed or damaged another 5,300 structures.