Firefighters are continuing to tackle a wildfire in northern California which has become the second largest in state history.
The Dixie Fire has already destroyed nearly all of the historic Gold Rush town of Greenville and authorities warn it could take weeks to contain.
There are currently 11 major wildfires burning in the state.
Rescue workers are bracing for higher temperatures of 38C (100F) in the coming days.
The Dixie Fire started on 13 July and has since ravaged more than 489,000 acres (198,000 hectares). Just 21% of the blaze is contained, according to officials.
It is second in size only to last year's August Complex fire, which burned through more than 1m acres, and is currently around 2.5 times the size of New York City.
Four people are missing and thousands have been evacuated, some of those now residing in tents. About 39% of Pumas County is under an evacuation order.
"We're seeing fire activity that even veteran firefighters haven't seen in their career," Edwin Zuniga, a spokesman for Cal Fire told the Washington Post.
"So we're just in really uncharted territory," he said.
More than 5,000 firefighters are currently tackling the Dixie Fire.
After ravaging through Greenville last Wednesday, the fire is now threatening the small town of Crescent Mills, three miles (five kilometres) southeast of Greenville.
Authorities have warned that low moisture levels have made the area vulnerable to fast-spreading fires.
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In a video briefing on Sunday, a California fire official said that living trees in the area now contain less moisture than a plank of wood bought at a lumberyard.
"It's that dry, so it doesn't take much for any sort of embers, sparks or small flaming front to get that going," said California Department of Forestry and Fire Protection section chief Mark Brunton.
According to the National Interagency Fire Center, there are wildfires across 15 states in the country. There are about 107 large blazes that have burned through more than two million acres.
It warned of a "high potential for severe wildfire activity throughout the western United States through the rest of summer and into the fall".
On Saturday, California's Governor Gavin Newsom said that "we need to acknowledge just straight up these are climate-induced wildfires".
Climate change increases the risk of the hot, dry weather that is likely to fuel wildfires.
The world has already warmed by about 1.2C since the industrial era began and temperatures will keep rising unless governments around the world make steep cuts to emissions.