The massive plume of smoke produced by the out-of-control King fire burning in Northern California is roughly the length of Illinois, Colorado and several East Coast states, weather officials said Thursday.
The roughly 71,000-acre fire, which is only 5% contained, exploded overnight just north of the community of Pollock Pines east of Sacramento, threatening 2,000 homes.
Authorities on Thursday announced the arrest of a man suspected of deliberately setting the fire. Officials said 37-year-old Wayne Huntsman was arrested Wednesday in Placerville and was being held on $10-million bail.
According to the U.S. Forest Service, firefighters were unable to safely approach the fire and observe its behavior because of "steep terrain, inaccessibility, variable wind direction, and darkness."
Spot fires were observed three miles ahead of the main blaze, officials added.
More than 3,300 firefighters were battling the blaze, which officials said was now costing $5 million a day to fight.
The Forest Service's Laurence Crabtree said there was no estimate for when the fire might be contained. The devastation caused by the fire prompted Gov. Jerry Brown to declare a state of emergency for El Dorado County.