Los Angeles, Jan 12 (AP) Firefighters raced on Saturday to cut off spreading wildfires before potentially strong winds return that could push the flames toward the world famous J Paul Getty Museum and the University of California, Los Angeles, while new evacuation warnings left more homeowners on edge.

A fierce battle against the flames was underway in Mandeville Canyon, home to Arnold Schwarzenegger and other celebrities not far from the Pacific coast, where swooping helicopters dumped water as the blaze charged downhill. Firefighters on the ground used hoses in an attempt to beat back leaping flames as thick smoke blanketed the chaparral-covered hillside.

At a briefing, CalFire Operations Chief Christian Litz said a main focus would be the Palisades Fire burning in the canyon area, not far from the UCLA campus.

County Supervisor Lindsey Horvath said the LA area "had another night of unimaginable terror and heartbreak, and even more Angelenos evacuated due to the northeast expansion of the Palisades Fire".

Only light breezes were fanning the flames, but the National Weather Service warned that locally strong Santa Ana winds -- the nemesis of firefighters -- could soon return. Those winds have been blamed for turning wildfires into infernos that levelled entire neighbourhoods in the LA area, where there has been no significant rainfall in more than eight months.

The fire also was threatening to jump over Interstate 405, a main traffic artery through the area, which could become a gateway to densely populated areas in the Hollywood Hills and San Fernando Valley.

Even as the fires spread, the grim work of sifting through the devastation continued Saturday, with teams conducting systematic grid searches with cadaver dogs, said Los Angeles County Sheriff Robert Luna. A family assistance centre also was being set up in Pasadena, said Luna, who urged residents to abide by curfews.

"We have people driving up and around trying to get in just to look. Stay away," he said.

The fires have consumed about 145 square kilometres. Tens of thousands of people remained under evacuation orders and new evacuations were ordered Friday evening in an area that includes part of Interstate 405 after a flare up on the eastern side of the Palisades Fire.

Since the fires first began popping up around a densely populated, 40-kilometre expanse north of downtown LA, they have burned more than 12,000 structures, a term that includes homes, apartment buildings, businesses, outbuildings and vehicles. No cause has been identified yet for the largest fires.

The fires are still burning but early estimates indicate the losses so far could make the wildfires the nation's costliest ever. A preliminary estimate by AccuWeather put the damage and economic losses so far between USD 135 billion and USD 150 billion.

On Friday, many residents returned in a state of shock. For some, it was a first look at the stark reality of what was lost as the region of 13 million people grapples with the ominous challenge of overcoming the disaster and rebuilding.

Bridget Berg, who was at work when she watched television coverage of her house in Altadena erupt in flames, came back for the first time with her family two days later "just to make it real".

Their feet crunched across the broken bits of what had been their home for 16 years.

Her kids sifted through debris on the sidewalk, finding a clay pot and a few keepsakes as they searched for Japanese wood prints they hoped to recover.

While some residents sifted through rubble for keepsakes, officials urged them not to, warning that the ash can contain lead, arsenic, asbestos and other harmful materials.

"If you're kicking that stuff up, you're breathing it in," said Chris Thomas, a spokesman for the unified incident command at the Palisades Fire.

Allegations of leadership failures and political blame have begun and so have investigations. Governor Gavin Newsom on Friday ordered state officials to determine why a 440 million-litre reservoir was out of service and some hydrants had run dry. Meanwhile, Los Angeles Fire Chief Kristin Crowley said city leadership failed her department by not providing enough money for firefighting. She also criticised the lack of water.

"When a firefighter comes up to a hydrant, we expect there's going to be water," she said.

At least 11 people have been killed, five in the Palisades Fire and six in the Eaton Fire, according to the LA County medical examiner's office. Officials said they expected that number to rise as cadaver dogs search levelled neighbourhoods and crews assess the devastation.

The disaster took homes from everyone. The government has not yet released figures on the cost of the damage, but private firms have estimated it will climb into the tens of billions.

Firefighters for the first time made progress Friday afternoon on the Eaton Fire north of Pasadena, which has burned more than 7,000 structures. Officials said most evacuation orders for the area had been lifted.

LA Mayor Karen Bass, who faces a critical test of her leadership as her city endures its greatest crisis in decades, said several smaller fires also were stopped.

Crews earlier Friday had been gaining ground on the Palisades Fire, which burned 5,300 structures and is the most destructive in LA's history.

California National Guard troops arrived on the streets of Altadena before dawn to help protect property in the fire evacuation zone, and evening curfews were in effect to prevent looting after several earlier arrests. (AP) SZM