© Chris Huber
The blaze, called the Cottonwood Fire, began around 1 p.m. Sunday and was initially battled by 300 firefighting personnel. The fire caused smoky skies and upset ranching activities across a wide swath of land about 75 miles east of Rapid City in an area between Interstate 90 and U.S. Highway 14.
No one had been injured by the fire or while battling it as of late Monday; the fire was reportedly 75 percent contained by 4 p.m. Monday, and potential rain in the area Monday night might help the firefighting cause.
Officials located the fire's point of origin and an investigator confirmed Monday that the fire was human-caused, but no specific cause was announced as the investigation continues, said Rapid City Fire Department Lt. Jim Bussell.
Sunday's fire-ripe combination of unseasonably high temperatures, low humidity and winds gusting as high as 50 mph pushed flames swiftly across the prairie, scorching most everything in its path.
"Under these conditions, the fire spread quickly," Bussell said in a Monday news briefing.
The fire scorched an estimated 48 square miles of private land and part of the Buffalo Gap National Grassland, southeast of Cottonwood and north of I-90.
Comment: To find out more about how sinkholes are formed and the dramatic increase we've observed recently, see: Sinkholes: The groundbreaking truth.
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