A Northern California wildfire near Yosemite National Park grew overnight to more than three times the size of San Francisco and spread inside the border of the park. Watch scenes near Yosemites.
The Rim Fire was caused when a hunter allowed an illegal fire to escape, the U.S. Forest Service said in announcing the cause of the devastating blaze that has been burning near Yosemite for more than two weeks.
No arrests have been made and the Forest Service isn't releasing the hunter's name pending further investigation.
On Wednesday, investigators shot down a theory that said it was started by an illegal pot grow. Jerry Snyder of the U.S. Forest Service said that the steep and inaccessible canyon where the Rim Fire started didn't have a water source that growers look for when they set up remote gardens. "The lead investigator says there's no evidence of any type of grow in the area where the fire started,'' Snyder said.
The Forest Service reiterated that Thursday saying there was no indication the hunter was involved with illegal marijuana cultivation on public lands and no marijuana cultivation sites were located near the origin of the fire.
The Rim Fire began Aug. 17, in the Stanislaus National Forest near the area known as Jawbone Ridge.
It has burned 237,341 acres and as of Thursday is 80 percent contained.
Officials said 111 structures, including 11 homes, have been destroyed. More than 4,300 firefighters are still battling the blaze.
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