Officials say the Oak Tree fire on State Route 83 near Sonoita, Arizona, began Wednesday around 1 p.m. when an RV caught fire and is around 20 percent contained.
Katie Goodwin, a spokeswoman for the Sonoita-Elgin Fire District, said that wind speeds are about 10 to 15 mph and are a factor in firefighting efforts. Other fire departments are also on scene.
A fire incident spokesperson said no structures are currently threatened. Authorities closed down a part of State Route 83 near the fire.
Officials believe the fire to be human caused.
No evacuations have been ordered.
Copyright 2015 The Associated Press modified.