A fast-moving wildfire near Yosemite National Park exploded in size Saturday and prompted evacuations even as firefighters made progress against an earlier blaze that burned to the edge of a grove of giant sequoias.

The Oak Fire, which began Friday afternoon southwest of the park near Midpines in Mariposa County, grew to 10.2 square miles by Saturday morning, according to the California Department of Forestry and Fire Protection, or Cal Fire.

As of Saturday morning, the fire had destroyed 10 residential and commercial structures and damaged five more, the Mercury News reported.

The fast-growing blaze prompted Caltrans to order numerous road closures, including a shutdown of Highway 140 between Carstens Road and Allred Road - blocking one of the main routes into Yosemite National Park.

Hot weather and bone dry vegetation caused by the worst drought in decades was fueling the blaze and challenging fire crews, said Daniel Patterson, a spokesman for the Sierra National Forest.

About 1,700 residents in the area were put under mandatory evacuation orders Friday night.