The Cold Springs Fire, which is west of Boulder, was sparked on Saturday and has since charred 536 acres.
It is zero percent contained.
Nearly 2,000 people have been evacuated, authorities said. Three homes have been gutted so far, including one of Nederland’s own firefighters, according to CNN affiliate KDVR.
“There’s not much left. It’s foundation and burning ashes,” Bretlyn Schmidtmann, wife of firefighter Charlie Schmidtmann, told the station.
Investigators say the fire began after the two men failed to properly put out a campfire.
They face felony arson charges because lives were endangered as a result of the fire.