Approximately 50 to 80 structures have been lost, including the National Park Service administrative buildings and visitor facilities.

U.S. land managers are racing the clock as hotter, drier weather raises the risk of wildfires in the nation’s overgrown forests with each passing year.

Arizona Governor Katie Hobbs has demanded an independent investigation into why National Park Service staff let the fire burn during the driest time of the summer in a botched attempt to reduce wildf...