For nearly a month, wildfires have burned their way through an area the size of London, and only a fifth of the blaze has been contained, ITV News Correspondent Neil Connery
The Dixie Fire raging in northern California has ballooned in size to become the largest single wildfire ever recorded in the state.
The largest active blaze in the US, it has burned through more than 463,000 acres, an area larger than Greater London.
Working tirelessly in unprecedented conditions, around 6,000 firefighters have been battling the flames to try and protect thousands of threatened properties in rural communities of the Sierra Nevada.
Thick smoke cleared for several hours along one edge of the Dixie Fire on Monday, allowing aircraft to join the mass of firefighters in the attack.
Many were battling to protect more than a dozen small mountain and rural communities in the northern Sierra Nevada.
“Today was the first day in a few days that we had good, clean air in there so we were able to use our helicopters,” allowing some progress, Kyle Jacobson, the east zone incident commander, said at an evening briefing.
The Dixie Fire, named for the road where it started on 13 July, has destroyed some 600 homes, forcing some to temporarily reside in tents as the huge firefighting effort continues.
Heat waves and historic drought tied to climate change have made wildfires harder to fight in the American West.
Rescue workers expect temperatures to reach 38C in the coming days, with authorities warning that low moisture levels have made the area vulnerable to fast-spreading fires.
The devastating fires have ripped through 463,000 acres of land
On Wednesday, the blaze effectively destroyed the historic gold rush town of Greenville, as it triggered evacuation orders to some 800 residents who were urged to leave before the inferno tore through the area.
A petrol station, hotel and museum and bar were among the sites consumed in the town, which contained some wooden buildings more than 100 years old."We lost Greenville tonight," said Congressman Doug LaMalfa, who represents the region.
Footage from Greenville shows the flames taking hold of buildings
Four firefighters were taken to the hospital Friday after being struck by a fallen branch.
More than 30 people were initially reported missing, but by Monday the Plumas County Sheriff’s Office had accounted for all of them.
Although the fire’s cause remains under investigation, California-based utility company Pacific Gas & Electric has said it may have been sparked when a tree fell on one of its power lines.
A federal judge ordered PG&E on Friday to give details by August 16 about the equipment and vegetation where the fire started.
There are an estimated 107 wildfires across 15 states in the country, according to the National Interagency Fire Center.
Northwest of the Dixie Fire in the Shasta-Trinity National Forest, hundreds of homes remained threatened by two fires that continued to grow.
About a third of the McFarland Fire was contained. New evacuation orders were issued Monday for residents near the Monument Fire, which was only about 3% contained.
South of the Dixie Fire, firefighters prevented further growth of the River Fire, which broke out Wednesday near the community of Colfax and destroyed 68 homes.