Millions of people across Southern California faced new wildfire warnings on Tuesday as strong winds blew across the parched landscape around Los Angeles.

The death toll from the fires which have been burning for a week has risen to at least 25 people, while tens of thousands saw their power shut off.

Santa Ana winds which began gusting over the mountains before sunrise were forecast to continue until Wednesday morning with enough force to carry fire-sparking embers for miles and stoke new outbreaks.

A search and rescue crew sifts through the wreckage of a home destroyed by the Eaton Fire in Altadena (John Locher/AP)

“Life threatening and destructive and widespread winds are already here,” LA city fire chief Kristin Crowley told a news conference.

Officials attributed one more death to the Eaton Fire, which has killed 17 people, on Tuesday. The Palisades Fire has killed eight.

The death toll is likely to rise, according to Los Angeles County Sheriff Robert Luna.

At least two dozen people were still missing, he said on Tuesday. Some people reported as missing earlier have been found.

Just under 90,000 people in the county remained under evacuation orders, half the number from last week.

Much of Southern California was under elevated fire risk, with crews on high alert from the Mexican border to Central California, far north of Los Angeles.

Backed by firefighters from other states, Canada and Mexico, crews were deployed to attack flare-ups or new blazes. The firefighting force was much bigger than a week ago, when the first wave of fires began destroying thousands of homes in what could become the nation’s costliest fire disaster.

Tuesday’s forecast included a rare warning: The winds, combined with severely dry conditions, have created a “ Particularly Dangerous Situation”, the National Weather Service said, meaning any new fire could explode in size.

Gusts were forecast to pick up strength in the evening and into Wednesday before decreasing, and red-flag warnings from Central California to the Mexican border were to remain through most of Wednesday, weather service meteorologist Ariel Cohen said.

Planes doused homes and hillsides with bright pink fire-retardant chemicals, while crews and fire engines deployed to particularly vulnerable spots with dry brush.

Los Angeles Mayor Karen Bass and other officials who were criticised over their initial response expressed confidence that the region is ready to face the new threat.

The mayor said she was able to fly over the disaster areas, which she described as resembling the aftermath of a “dry hurricane”.

“While we are going through what I hope is the final hours of this disaster, we need to start thinking about our recovery,” Ms Bass said.

One step the mayor took this week should make 1,200 housing units available quickly. She said they were ready before the fires, but were caught up in getting regulatory approval.

A cat wanders amid cars destroyed by the Eaton Fire in Altadena (Chris Pizzello/AP)

Winds this time were not expected to reach the same fierce speeds seen last week but could ground firefighting aircraft, LA County fire chief Anthony Marrone said, warning that if winds reach 70mph, “it’s going to be very difficult to contain that fire”.

He urged homeless people to avoid starting fires for warmth and to seek shelter.

Nearly 90,000 households lost electricity as utilities shut off power to prevent their lines from sparking new blazes.

Police have announced roughly 50 arrests for looting, flying drones in fire zones, violating curfew and other crimes.

Three people were arrested on suspicion of arson after being seen setting small fires that were immediately extinguished, LA Police chief Jim McDonnell said. One was using a barbecue lighter, another ignited brush and a third tried to light up a trash can, he said. All were far outside the disaster zones.

Authorities have not determined a cause for any of the major fires.

Among nine people charged with looting was a group that stole an Emmy from an evacuated house, Los Angeles County district attorney Nathan Hochman said.

Hollywood’s awards season has been put on hiatus because of the crisis. The Oscar nominations have been delayed twice, and some organisations postponed their awards shows and announcements without rescheduling.