President Donald Trump expressed sadness on Saturday (Nov 17) at the devastation in a California town, as more than 1,000 people remain listed as missing in the worst-ever wildfire to hit the U.S. state.

President Donald Trump talks with California Governor-elect Gavin Newsom and Paradise Mayor Jody Jones during a visit to a neighbourhood destroyed by the wildfires on Nov 17, 2018, in Paradise, California. (Photo: AP/Evan Vucci)

Two huge blazes have created a serious smoke problem across vast areas in the state, and when Trump stepped out of Air Force One at Beale Air Force Base north of capital city Sacramento, the sun was struggling to cut through haze so dense it covered the base like a fog.

"This is very sad," Trump said after surveying the remains of Paradise, where nearly the only people out on the road were emergency services workers, surrounded by the twisted remains of the incinerated town.

"They're telling me this is not as bad as some areas; some areas are even beyond this, they're just charred," he added after looking at a street lined with melted cars, tree stumps and the foundations of wrecked houses.

The deadliest and most destructive wildfire in California's history, the so-called Camp Fire, has now claimed 71 lives.

The fire has devoured an area roughly the size of Chicago, destroying nearly 10,000 homes and 2,400 other buildings.

In this aerial photo, a burned neighborhood is seen in Paradise, California on November 15, 2018. (Photo: AFP/Josh Edelson)

Butte County Sheriff Kory Honea told reporters the number of people unaccounted for had soared, from 631 to 1,011, in 24 hours as authorities received more reports of people missing, and after earlier emergency calls were reviewed.

"I want you to understand that this is a dynamic list," Honea told reporters, noting there could be duplicates and some people who had escaped could be unaware they were listed as missing.

Some 329 people who had been listed as missing have now been found.

The inferno erupted Nov 8, laying waste to Paradise in the northern foothills of the Sierra Nevada mountains and sending thousands fleeing.

'FOREST MANAGEMENT' DISPUTE

The president was accompanied on his visit by chief of staff John Kelly and Trump son-in-law Jared Kushner.

They were met on the tarmac by Governor Jerry Brown and Governor-elect Gavin Newsom, both of them Democrats in a state that leans strongly that way.

Along his drive, several signs thanked Trump for coming but one called him a "moron."

In Chico, near Paradise, Trump met with firefighters and other first responders at makeshift headquarters for emergency services.

High-ranking fire officials recounted how quickly the fire spread, complicating evacuation efforts, as Trump studied a huge map spread across a table showing where fires continue to burn.

Keeping alive an earlier controversy, Trump repeated his claim that California had mismanaged its forests and was largely to blame for the fires.

"I'm committed to make sure that we get all of this cleaned out and protected, (we've) got to take care of the forest, it's very important," Trump said in Paradise.

Brian Rice, president of California Professional Firefighters, called Trump's earlier remarks "ill-informed," noting the federal government had cut spending on forest management.

Asked if he believed climate change had played any role in the fires, Trump again pointed to the forest "management factor" and insisted that his "strong opinion" - he has been skeptical of man's role in global warming - remained unchanged.

Roslyn Roberts, 73, who was forced from her home in Paradise, said she voted for Trump but disagrees with him.

"I would tell him that this fire has nothing to do with forest mismanagement. Thousands and thousands of homes got destroyed with no trees around," she said at a shelter set up by the American Red Cross in a church.

In Chico, just west of Paradise, volunteers had erected a tented encampment for evacuees.

Tents are seen pitched in a field next to a Walmart parking lot where Camp Fire evacuees have been staying on Nov 16, 2018 in Chico, California. (Photo: Justin Sullivan/Getty Images/AFP)

"Just trying to make it day by day. It's all we can do," said Dustin Kimball, who worked at the Paradise cemetery.

The Camp Fire has burned 148,000 acres (60,000 hectares) and was 55 per cent contained by Saturday, California's fire service said.

Authorities said 47,200 people had been evacuated because of the fire and nearly 1,200 were living in shelters.

Smoke from the fire forced schools to close in San Francisco on Friday and the city's iconic cable cars had to suspend service. The Golden Gate Bridge was shrouded in thick smog.

LOSING HOPE

Much of the rescue work is now focused on Paradise, where many retirees were unable to get out in time.

Rescuers with sniffer dogs have been conducting a painstaking house-to-house search.

"I'm still going to keep on looking and hope for the best," Jhonathan Clark told AFP. He was hunting for his brother, sister-in-law and nephew.

Three other people have died in southern California in a blaze dubbed the Woolsey Fire, which engulfed parts of Malibu, destroying the homes of several celebrities.

That inferno, which is about two thirds the size of the Camp Fire, was 82 per cent contained on Saturday.

Adding to the misery of Camp Fire survivors, an outbreak of the highly contagious norovirus has been reported at several shelters. Twenty-five people had to be hospitalised, health officials said.

While the cause of the Camp Fire remains under investigation, a lawsuit has been filed against the local power company, PG&E, by fire victims claiming negligence./.

VNF/AFP