A 37-year-old man has been arrested on suspicion of arson in connection with the largest of three wildfires that have devastated Spokane, Washington state, forcing more than 60,000 people to evacuate. Aaron Farinacci was allegedly seen kneeling near grass at the site of the Old Trails fire and was later found carrying matches and a lighter; he has been charged with first-degree arson and held on a $1m bond. Washington's governor described the situation as a "nightmare" and likely the worst natural disaster in Spokane's history, though no deaths or injuries have so far been confirmed.

More than 700 buildings have been destroyed and a further 400 are yet to be assessed, with thousands of acres burned across the three fires – Old Trails, Fairview and Autumn Lane – which form part of 16 wildfires currently burning across the state. Authorities are trying to reach 14 people who have not answered their phones, though officials believe most likely evacuated safely but lost signal or battery power. More than 900 firefighters have been deployed, with reinforcements en route, while the governor has imposed a statewide ban on outdoor fires amid warnings that hot, dry, windy conditions – linked to climate change – could fuel further blazes later in the week.