Fire crews are gaining on a wildfire that started Saturday afternoon in Rose Canyon and prompted voluntary evacuations of more than 430 nearby homes, according to Unified Fire Authority.

Crews arrived at the fire about 3 p.m. Saturday near 8030 Step Mountain Road in Herriman. At the scene, they saw flames and the potential for spreading, so they asked all residents living immediately south and west of 14100 S. Shaggy Mountain Road to evacuate.

By Saturday afternoon, crews had gotten a handle on the blaze, and they lifted evacuation orders and road closures by 8:30 p.m.

Officials suspect lightning sparked the fire. It has burned through about 6 acres of grass and juniper. Forty firefighters and two helicopters were called to the scene.