Firefighters spent a second day in scorching heat Sunday battling wildfires that destroyed 30 buildings and burned more than 7,000 acres of Southern California brush and forestland.

Several of the most destructive blazes were contained by early morning, but at least two others burned out of control in the area’s vast national forests.

Most of the fires erupted Saturday during a heat wave in which temperatures climbed close to 100. On Sunday, another fire broke out as temperatures again rose into the 90s.

A 4,500-acre fire raced out of control in the village of Pine Cove in Riverside County. No injuries were reported and no residents were asked to evacuate, said Lenore Will, a spokeswoman for the U.S. Forest Service.