Authorities in Colorado have identified two causes that led to the most destructive wildfire in the state’s history.
The Boulder County Sheriff’s Office concluded its 18-month investigation into the 2021 Marshall Fire, announcing June 8 that the fire had been formed from two separate fires. One of those started at a residential property where a legal burn that had been done six days earlier was reignited by high winds. The other fire, which ignited about one hour after the first, was caused by arcing power lines. Prosecutors have opted to file no criminal charges.