The fire sparked in the Los Padres National Forest in San Luis Obispo County and was growing exponentially, officials warned. The area is mostly uninhabited.

A wildfire in California’s San Luis Obispo County rapidly expanded overnight and was covering more than 52,600 acres by Thursday afternoon, prompting evacuation orders, closing part of a highway and sending thick smoke billowing into neighboring counties.

The Madre Fire has continued to blaze through Central California, mapping at 35,530 acres with 5% containment as of Thursday morning. There are no known injuries reported and the fire is threatening 50 structures,