A wildfire at North Carolina's Pilot Mountain State Park had grown to more than 1,000 acres (400 hectares) by Tuesday afternoon, twice its size of a day earlier, authoritiess said.
Officials said the blaze, which has burned more than 1,050 acres on Pilot Mountain, is about 20% contained and is burning only inside the park, news outlets reported.
Compounding the situation is that the area has received only 0.3 inches of rain in November with no significant prospect for precipitation for the rest of the week. Average rainfall for November is 3 inches (7.6 cm)
The park, northwest of Winston-Salem, is known for its iconic knob that rises about 1,500 feet (450 meters) above the surrounding terrain. It also towers above nearby U.S. Highway 52, and officials are advising motorists to slow down and turn on their headlights in smoky conditions.
N.C. Forest Service officials believe the fire, which started near a trail on Saturday, was caused by human activity, according to Jimmy Holt, forest service ranger for Guilford County.
He said law enforcement will investigate to determine what sparked the blaze. The park remains closed.
Officials issued a statewide outdoor burning ban Monday, citing dry conditions across the state.
