Authorities in the city of Spokane, in the northwestern United States, are working Tuesday to extinguish three voracious wildfires that have forced more than 65,000 people to flee their homes and reduced hundreds of buildings to ashes.

The flames, fueled by drought and intense heat in the vicinity of this city of approximately 260,000 residents, have already burned thousands of acres and damaged vital infrastructure, while anxious families await word on when they may return.

A 37-year-old man identified as Aaron Farinacci was arrested as a suspect in connection with starting the largest of the three fires and was held on $1 million bail after a witness reportedly saw him kneeling near the location where the blaze began, Spokane County Sheriff John Nowels said at a late Monday news conference.

Farinacci was initially detained near the site where the fire started on Saturday but was released, before being taken into custody again after officers linked him to the case, Nowels said.

According to InciWeb, a federal information system, the three fires have collectively burned 3,248 hectares in the Spokane area. Firefighters have taken advantage of a reprieve from the heat to make "significant progress" against two of the blazes.

Aerial surveys, however, revealed that between 700 and 1,110 structures have been lost since the fires erupted over the weekend, according to authorities. No fatalities or injuries have been reported to date.

Cooler temperatures are also expected on Tuesday, though the respite will be brief, as high temperatures exceeding 30 degrees Celsius are forecast to resume by midweek.

Video footage of the fire's aftermath on Sunday showed dozens of homes reduced to ashes, while other nearby residences emerged virtually unscathed. "Just driving through there and seeing the houses... it's one of the most heartbreaking things I have ever seen in my life," Spokane resident Geoff Beadles told AFP after evacuating his home with his fiancée and two dogs.

Authorities are working to locate 14 individuals with whom they have been unable to make cell phone contact, though they are not yet considered missing, Nowels said. "I think the estimate is up to 65,000 people that we had to evacuate from these areas, and if you think about what that entails, the fact that we were able to get people out of those areas in a few hours in an active fire zone is pretty incredible," the sheriff stated.

Spokane Mayor Lisa Brown said authorities were combing the city block by block to assess damage and noted that no date has been set for residents to return home. "It could be weeks, depending on where your home and property are located," she said.

Washington State Governor Bob Ferguson described the fires as "the worst natural disaster" in Spokane's history. Ferguson, who spoke with President Donald Trump about the situation, declared a state of emergency on August 1, citing drought conditions and high temperatures that are exacerbating the wildfires.

Experts point out that climate change caused by human activity is creating increasingly favorable conditions for more frequent and intense wildfires. This, in turn, generates a vicious cycle: the increase in such fires releases massive amounts of carbon dioxide into the atmosphere, accelerating planetary warming.

The Spokane fires follow "one of the warmest winters on record in eastern Washington," which produced a severe snow drought, said Daniel Swain, a climatologist at the University of California. Washington State Department of Natural Resources Director David Upthegrove noted that the Spokane fires were among the 16 most significant blazes burning across the state, covering more than 1,000 square kilometers. "This is not a normal season" for fires, he emphasized.

A power outage map published by local utility provider Avista showed that, as of late Monday, more than 3,700 customers were without electricity due to the emergency.