(KGTV) — More than 20,000 acres have been scorched in Riverside and San Bernardino Counties by the Apple Fire since Friday, prompting evacuation orders for thousands of residents.
The fire had burned 26,450 acres and was 5% contained as of Monday at 7:48 a.m., according to Cal Fire.
Officials say the blaze began as two separate fires on Friday in Cherry Valley, an unincorporated area near Beaumont in Riverside County, before exploding over the weekend and crossing into San Bernardino County.
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The U.S. Forest Service says the majority of the area covering the northern and eastern edges of the fire is very steep and rugged, making it difficult for crews to access the area with vehicles. The agency added that a high pressure ridge on Sunday created hot and dry conditions, fueling the flames.
Helicopters and fixed-wing air tankers were assisting ground crews and equipment in battling the fire.
At least one home and two outbuildings have been destroyed by the fire and several more were threatened. No injuries have been reported.
Evacuation updates for Riverside County were posted here, while evacuation updates for San Bernardino County could be found here.
A plume of smoke could be seen for miles and led to air quality warnings.
The cause of the fire is still under investigation.