An explosive and erratic wildfire grew to more than 100 square miles in Northern California on Saturday, threatening thousands of structures and forcing hundreds of people into evacuation centers.
The so-called Butte Fire, burning in Calaveras and Amador counties, began Wednesday, scorching only 100 acres. But the flames kept up their momentum overnight Friday, ballooning from 32,000 acres to 65,000 acres by Saturday morning, said Dan Berlant, of the California Department of Fire and Forestry Protection, or Cal Fire.
The fire destroyed 86 homes and 51 outbuildings by Saturday evening, and 6,400 other structures were threatened, Cal Fire said. It was 15 percent contained.
The 2,700 residents of San Andreas, about 60 miles southeast of Sacramento, were placed under mandatory evacuation orders on Friday night before the fire switched directions and the order was lifted. But they were warned that they may need to leave at a moment's notice depending on the fire's trajectory.
Hundreds of people from other surrounding communities were ordered to flee their homes and quickly filled up evacuation centers, one of which had to change locations twice as the fire's path zigzagged.
One of four evacuation centers was set up by the Red Cross in San Andreas before it needed to be moved Friday to the Calaveras County Fairgrounds due to overcrowding.
As the fire moved toward the fairgrounds, the center was once again shifted — this time to the Jackson Rancheria Casino Resort in Amador County. More than 200 people stayed there overnight Friday, according to the Red Cross.
Sean White, 48, lives in Rail Road Flat, north of San Andreas, and said he didn't need to be told to leave his home. He said there was no question that he would evacuate after his "family saw flames, raining ash, chaos, neighbors, police and fire."
Gov. Jerry Brown issued a state of emergency Friday in Calaveras and Amador counties.
Steep terrain and dry conditions were hampering efforts of the more than 3,800 firefighters striving to beat the blaze, but a break in sweltering temperatures allowed crews to increase containment from 5 percent to 15 percent by Saturday night, Cal Fire reported.
Air quality conditions still remained a hazard Saturday in the areas surrounding the Butte Fire, which was one of a dozen burning in the drought-stricken state.
A large swath of the center of California was under an air quality alert due to several of the blazes, according to the National Weather Service.
White told NBC News that the areas surrounding the Butte Fire are even "dark in the day, with lights on."
"Reminded me of an eclipse when it gets dark," White said.
Ali Gostanian contributed to this report.