wildfire in southern California, which has been deemed the Apple fire, has forced evacuation orders in several neighborhoods after burning more than 4,000 acres and destroying at least one home Saturday.

The fire, which started in Riverside, an area roughly 75 miles from Los Angeles, is said to be zero percent contained even though 375 firefighters, dozens of engines and air support are on the scene.

Evacuation warnings and orders have been set for the Potato Canyon and the Oak Glen areas, as the fire has moved into San Bernardino County, according to the California Department of Forestry and Fire Protection (CAL FIRE) on Saturday.

“Approximately 2,586 homes totaling approximately 7,800 people are under evacuation orders,” the Riverside Fire Department tweeted Saturday evening.

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The fire was first reported to responders Friday afternoon, but the cause of the fire is still under investigation. One house and two structures have reportedly been destroyed.

Firefighters are working in extreme heat, with temperatures reaching up to 103 degrees in Riverside and 104 degrees in San Bernardino, according to the National Weather Service.

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CAL FIRE could not immediately be reached for comment.

An excessive heat warning has also been issued in San Bernardino and Riverside County valleys, advising people to stay out of the sun, drink plenty of fluids and to check up on relatives of neighbors -- noting that leaving children and pets in cars during the heat warning is strictly disallowed.

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The National Weather Service has warned that hot and dry weather is expected through the next week, and winds are expected to be around 16 mph through the evening, with it becoming less windy through the beginning of the week.

Southern California experiences fire hazards well into the fall season.