BOISE, Idaho (AP) - A wildfire threatening nearly a dozen structures in southwestern Idaho appears to have been caused by a utility vehicle that caught fire along a roadway, authorities said Tuesday.
Crews were preparing for a long battle against the Trinity Ridge Fire, which spread to 3,300 acres in the Boise National Forest, while to the west, 200 firefighters were challenged by hot temperatures and gusty winds while working to contain the fast-growing Springs Fire near Banks, along Highway 17.
The Trinity Ridge Fire started Friday about 50 miles east of Boise and could potentially grow very large because of dry conditions, the terrain and the abundance of sub-alpine fur and lodgepole pine in the region, said forest spokesman Dave Olson.
"This is a very challenging type of fuel to fight fire in," he said.
The trees are prone to torching and throwing embers that can start new fires, which impeded efforts to contain the blaze over the weekend before it spread. The blaze expanded Saturday despite nearly 50 runs by four military C-130 cargo planes based at the nearby Boise Air Terminal and more drops by three single-engine air tankers.
The fire, which is 10 miles northwest of Featherville in Elmore County, was 1 percent contained and threatening 11 outbuildings.
Officials briefed local residents Tuesday in the town of Pine.
"They told them that we're dealing with a tough fire, it's going to take quite a long time to suppress it," Olson said. "It could be weeks."
A community meeting was also scheduled in the central Idaho town of Stanley, which is less than 20 miles from the largest of the state's eight wildfires, according to the National Interagency Fire Center. The Halstead Fire in the Frank Church River of No Return Wilderness has spread to more than 50 square miles since it started burning in late July and containment is not expected until this fall.
The blaze was caused by lightning.
Back in southwestern Idaho, the Springs Fire was burning on 1,400 acres of grass, brush and timber near Banks.
The human-caused fire was 30 percent contained early Tuesday and rafters on the South Fork of the Payette River were cautioned that in some areas, helicopters were dipping to retrieve water to dump on the blaze.
Authorities condensed traffic into one lane along several miles of Highway 17 and along a shorter stretch of Highway 55, Olson said.
The wildfire was expected to be fully contained on Wednesday.
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