![gasoline fire](https://ticklethewire.com/wp-content/uploads/2010/06/explosion-2-300x198.jpg)
The FBI is joining local authorities in trying to determine what caused the Colorado wildfires that swept through Waldo Canyon, the Denver Post reports.
The fire started near a popular hiking area west of Colorado Springs.
Authorities aren’t sure what caused the fire or whether it was intentionally set, the Post reported.