Wildfires have forced around 60,000 people to evacuate parts of the north-western US state of Washington, destroying hundreds of buildings and leaving thousands without power.

Three major blazes continued to burn around the city of Spokane on Monday, with officials warning the fires had not been contained.

Spokane Mayor Lisa Brown described the situation to the BBC as “the worst natural disaster our region has faced”, adding that authorities were assessing the extent of the damage and were “still discussing the potential for lives to be lost”.

No deaths or injuries have been confirmed. Investigators have yet to work out how the blazes started.

The fires in Spokane are among a total number of 16 large, uncontained wildfires on the landscape in Washington state as of Monday morning, according to the state’s department of natural resources.

The National Weather Service (NWS) had warned of “extremely critical” fire weather over the weekend, with strong winds and unusually dry conditions helping the flames spread rapidly.

Videos from Spokane – the second most populous city in the state – show huge plumes of smoke and roaring fires tearing through houses, as helicopters fly above trying to put out the flames.

The fires have destroyed around 700 buildings, including homes, businesses and other buildings.

More than 10,000 electricity customers were left without power on Sunday, according to Avista Utilities. By Monday, around half of them had their power restored.

Washington State Governor Bob Ferguson has declared a statewide emergency and requested federal assistance after speaking with US President Donald Trump.

The three fires around Spokane – Old Trails, Fairview and Autumn Lane – have been together named the Spokane Complex Fires. Fuelled by high winds, the fire jumped over the Spokane River at least twice, officials say.

At a news conference on Monday, one official said the burned area looks like a “war zone”.

Maj Gen Gent Welsh, who commands the state’s National Guard, said the scene reminded him of his time serving in the US military in Iraq.

“I can tell you today that that’s a war zone,” he said. “When you finally get in there, and you finally look at the devastation and the damage.”

Spokane County Sheriff John Nowels said that officials were trying to contact 14 people to confirm they managed to safely evacuate.

Speaking to the BBC, Mayor Brown said: “The most important thing is that people need to remain vigilant and be patient and comply when we ask them to be ready to evacuate or when we say it’s time to evacuate.”

Although lighter winds are expected, forecasters have warned temperatures are likely to rise again later in the week.

On Monday, Gov Ferguson issued a statewide ban on all outdoor fires.

Commissioner of Public Lands Dave Upthegrove in a written statement: “Our firefighters are already stretched thin across the state, and with more heat and wind expected this weekend and for the rest of the summer, any new spark on our tinder dry landscapes can lead to another devastating wildfire.

“I’m urging all Washingtonians to not be that spark.”

More than 900 firefighters are currently assigned to the blazes in Washington, with more reinforcements expected to arrive from other states in the coming days.

Officials are reminding the public that it is illegal to fly drones near the fires, because they interfere with firefighting planes and helicopters and force them to land. Drones disrupted operations 26 times on Sunday.

Scientists have said that human-induced climate change makes the warm, dry conditions that lead to wildfires more likely – as well as leading to more frequent and intense heatwaves, and potential summer droughts.