US President Donald Trump has declared a "major disaster" in California and ordered federal funding to be made available to help recovery efforts in areas affected by wildfires.
In a statement, the White House said that Mr Trump had "ordered Federal assistance to supplement State, tribal, and local recovery efforts in the areas affected by wildfires and high winds beginning on 23 July 2018, and continuing".
It comes after officials said that a seventh person died in a northern California wildfire, as further fast-growing wildfires in the state expanded by more than 25% overnight and continued to spread.
More residents were ordered to evacuate their homes as weary firefighters endured high temperatures and gusting winds.
The Carr fire, about 261km north of Sacramento, claimed the life of a power company lineman yesterday, according to a CBS affiliate citing a spokesman for the PG&E Corporation.
Neither a spokesman with the electric company nor fire officials were immediately available for comment.
No other details about the death were made public.
The Carr fire, one of the most destructive in California history, had already killed six people, including a great-grandmother and two children, and a firefighter and bulldozer operator.
Two other blazes collectively called the Mendocino Complex burned in Mendocino, Lake and Colusa counties, about 144km north of San Francisco.
The River and Ranch fires had grown to cover a total of 229,000 acres by early yesterday, and were considered 34% contained.
The scorched land figure is expected to rise when the California Department of Forestry and Fire Protection (Cal Fire) issues an update, a spokeswoman said.
This year, California wildfires have burned more land earlier in the "fire season" than usual, said Ken Pimlott, Cal Fire director, during a news conference yesterday.
"Fire season is really just beginning. What seems like we should be in the peak of fire season, historically, is really now the kind of conditions we're seeing really at the beginning," he said.
California Governor Jerry Brown, who visited some of the burned areas on yesterday, said, "This is part of a trend, the new normal, that we've got to deal with."
Through last week, California fires had torched about 290,000 acres, more than double the five-year average over that same period, according to Cal Fire.
The Mendocino Complex fires cover more than two-thirds the size of sprawling Los Angeles. They have forced the evacuation of more than 20,000 residents and destroyed more than 100 structures.
More evacuations were ordered on yesterday afternoon, but no estimate of people involved was released.
The Mendocino Complex fires have swelled to become larger than the deadly Carr Fire, about 160km to the northeast, which has killed at least six people and destroyed more than1,500 structures.
Firefighters by Saturday morning had managed to contain 41% of the Carr blaze and authorities were allowing some evacuees to return, Cal Fire said.
Both areas remained under a "red flag warning" issued by the National Weather Service for strong winds, low relative humidity and temperatures topping 32C, all conditions that can drive the growth of wildfires.
So far this year, US fires have burned five million acres, much more than the ten-year average, according to the National Interagency Fire Center.
