Despite the ferocity of the flames Monday afternoon, it appeared that only several homes were damaged or destroyed in San Bernardino, about 60 miles (97 kilometers) east of Los Angeles, said Eric Sherwin, spokesperson for the San Bernardino County Fire Department.

One firefighter was treated for a minor injury but there were no reports of injuries to residents.

“How quickly this fire hit this community,” Sherwin said, “the fact that we have no civilians injured is truly a miracle.”

The fire was reported at 2:40 p.m. Monday and stopped progressing about three hours later after scorching 54 acres (22 hectares). Containment was holding at 75%, Sherwin said. Homes on three streets remained under evacuation orders.

Investigators were working to determine the cause of the fire, which erupted amid very dry and hot conditions that have made swaths of California quick to burn this summer.

In Northern California, firefighters battled the reawakened Park Fire, a massive blaze that re-exploded Monday after several days of slumber and grew by as much as 20 square miles (53 square kilometers), mostly in about 12 hours.

The Park Fire, California’s largest so far this year and the state’s fourth-largest on record, had already scorched nearly 647 square miles (1,676 square kilometers) by Tuesday morning.

Firefighters were told during their morning briefing to focus on safety and to be mindful of extreme fire behavior including intense and rapidly moving flames.

The Park Fire was allegedly ignited by arson on July 24 outside the Sacramento Valley city of Chico, and has destroyed 640 structures and damaged 52.