AlQa'dah 28, 1436, Sep 12, 2015, SPA -- Firefighters gained some ground Saturday against an explosive wildfire that incinerated buildings and chased hundreds of people from mountain communities in drought-stricken Northern California. The blaze exploded to more than 100 square miles (260 square kilometers) in two days, but crews increased containment to 10 percent overnight, AP quoted state fire officials as saying. Fifteen structures were destroyed, and about 6,400 others were threatened. Bright orange flames burning in the hills were visible from the edge of San Andreas, a gold-rush town about 60 miles (96 kilometers) southeast of Sacramento whose 2,700 residents were all told to evacuate briefly Friday before the fire shifted and they were allowed to stay for now. But hundreds of people from smaller surrounding communities fled their homes and filled up evacuation centers, one of which had to be moved twice to get it a safe distance from the flames.