Smoke from the Rim Fire as seen from a webcam perched at the Crane Flat Lookout on Aug. 29, 2013.
Investigators have determined the cause of the wildfire that's been raging in California near and in part of Yosemite National Park. The U.S. Forest Service announced Thursday (Sept. 5) that the blaze was started when a hunter allowed an illegal fire to escape.
Officials also shut down speculation that the so-called Rim Fire was linked to a marijuana farm.
"There is 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," a statement from the Forest Service said.
The hunter's name is being withheld from the public pending further investigation. Officials added that no arrests have been made yet.
The Rim Fire was sparked on Aug. 17 in the Stanislaus National Forest, next to Yosemite, and rapidly spread. It has burned 237,341 acres (96,048 hectares) and fire crews currently have 80 percent of the blaze contained.
The wildfire, which prompted road closures and evacuations in the region, has threatened homes, Yosemite National Park and San Francisco's water supply. Its smoke could even be seen from space. NASA astronaut Karen Nyberg took a picture of the plumes from her post aboard the International Space Station.