A ridge-top fire above Thunderhead Falls Road in the Hisega area had burned about 1-1/2 acres of Black Hills National Forest land before 10 p.m. Wednesday.

Crews from the South Dakota Wildland Fire Suppression Division, the Mystic District of the Forest Service and volunteers from Johnson Siding and Whispering Pines fire departments were on the scene. The fire was reported at 6:45 p.m. and was clearly visible from along S.D. Highway 44 at Pioneer Road at Hisega.

A Great Plains Interagency Dispatch Center dispatcher said the 20 firefighters had to hike 45 minutes to an hour over steep, heavily wooded terrain to reach the site. The fire was staying on the ground, with flames 4 inches to 6 inches high.

Initial evaluation indicated a slight chance of the fire spreading. However, there were no nearby buildings or other infrastructure immediately at risk. The dispatcher said the fire's cause was not known.