An emergency has been declared in Washington state, where 60,000 people have been left without power as strong winds and high temperatures drive fast-moving wildfires.
More than 250,000 acres are burning in 12 large fires, with both the National Guard and firefighters from more than a dozen states tackling the blazes.
The US National Weather Service issued an unprecedented "particularly dangerous situation" red flag alert for eastern Washington on Saturday, rating the weather risk as"extreme".
Governor Bob Ferguson said: "Our record-setting drought and high winds are creating dangerous conditions across the state.
"I am declaring an emergency to help prevent loss of life and property damage. I encourage all Washingtonians to do their part to protect our state during these extreme conditions."
Spokane mayor Lisa Brown said thousands of people have been evacuated from their homes - with the figure expected to rise.
Around 60,000 people have been left without power, according to the Washington State Emergency Management Division.
No injuries or fatalities have been reported at this point, but officials say some buildings have been destroyed.
Major General Gent Welsh, adjutant general of the Washington National Guard, said: "When the sun sets and the sun rises in the morning, I think we're going to be in shock to see some of the scenes that emerged out there."
Outdoor and agricultural burning has been banned until the end of September, and it's unlawful to sell or discharge fireworks outside of licensed fireworks displays.
Washington's commissioner of public lands, Dave Upthegrove, said it has already been one of the busiest wildfire years on record, adding: "This is not normal… Throughout the state of Washington we're seeing fires raging."
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Washington is in the midst of a statewide drought for a record-breaking fourth year in a row.
More than 1,000 fires have burned approximately 425,000 acres - the most acres burned since 2021, according to the Department of Natural Resources.
Wildfires have also been a problem in other parts of the Pacific Northwest this summer, with nearly 34,000 lightning strikes last month leading to a series of fires and evacuation orders in the southern part of British Columbia.
(c) Sky News 2026: Washington state declares emergency as fast-moving wildfires see thousands evacuated
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