The Thirtymile Fire was first reported on July 9, 2001 in the Okanogan National Forest, approximately north of Winthrop, Washington, United States. The wildfire had been caused by an unattended campfire that spread rapidly in the hot and dry weather in the Pacific Northwest. Four firefighters were killed when the fire cut off their only escape route out of the narrow canyon. The fire burned of forest land dominated by Douglas-fir and lodgepole pine trees in the Chewuch River canyon. More than a thousand firefighters were involved in suppressing the fire, which was declared contained on July 23, 2001. Suppression costs ran US$4.5million. A Forest Service investigation found that numerous safety procedures were violated leading up to the fatal entrapment: fire managers repeatedly underestimated the potential danger of the situation and failed to establish and maintain escape routes and safety zones. Incident commander Ellreese Daniels was later charged with involuntary manslaughter and making false statements to investigators. Daniels pleaded guilty to two misdemeanor charges of making false statements to investigators as part of a plea deal; he was sentenced to three months of work release. Environmental conditions The fire began in the Chewuch River canyon about north of Winthrop, Washington. The canyon—located in the Okanogan National Forest—runs from northeast to southwest, with steep slopes of approximately . The canyon floor near the point of origin is about wide. Fuels in the canyon included spruce, Douglas-fir, lodgepole pine and cottonwood trees at the canyon floor and Doug-fir, lodgepole, and ponderosa pine on the canyon slopes. A single dead-end road follows the canyon upriver and leads to the Thirtymile Campground. High temperatures, low humidity, and extended drought conditions combined to create the potential for extreme fire behavior. The winter of 2000–2001 was the area's second-driest winter in 30 years, and on July 10, 2001 temperatures in the canyon reached and relative humidity dropped to about 8%—both near-historic extremes for the area. On July 9, the Libby South Fire was accidentally ignited by the exhaust system of a fire patrol vehicle about south of Winthrop. The fire grew to over by that evening, making it the first major North Cascades wildfire of the season. Firefighting response Initial attack The Thirtymile Fire was first reported at 9:26pm Pacific Daylight Time on July 9, 2001 by a Canadian firefighting aircraft returning to Canada after working on the Libby South Fire. A small firefighting crew was