An official says people shooting at targets ignited the 9,155-acre Weber Fire burning in southwest Colorado.
People were taking target practice on federal land Friday afternoon when a bullet passed through a target, ricocheted off a rock and landed in dry vegetation, starting the fire, said Butch Knowlton, director of La Plata County's Office of Emergency Preparedness, according to the Durango Herald.
However, federal and local investigators say while the fire is human-caused, the target practice report has not been confirmed.
"That is complete rumor," Montezuma County Sheriff Dennis Spruell told the newspaper.
Federal officials say this year alone there have been 20 target shooting-caused wildfires in Utah, including a fire near Saratoga Springs that forced the evacuation of 2,300 homes last week.
Earlier this month, a law enforcement official said people shooting at "explosive targets" sparked the Springer Fire in Park County, Colo.
Meanwhile, the Weber Fire continued to burn Wednesday in southeast of Mancos, in Montezuma County.
The fire is 30 percent contained.
More than 500 firefighters are battling the blaze, supported by four helicopters dropping water, U.S. Forestry Service officials said.
No homes have been lost.
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