As firefighters continue to battle the Nixon Fire in the Aguanga community of Riverside County, fire investigators determined an electrical device caused the blaze, Cal Fire announced Friday.
The Nixon Fire, which was first reported Monday afternoon, scorched 5,222 acres with 21% of it being contained as of Friday afternoon.
Cal Fire officials said its investigation determined the brush fire was caused by a “privately owned electrical panel” without providing further details.
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More than 1,000 personnel have been trying to extinguish and contain the fire, which destroyed four structures, including at least one home.
Evacuation orders and warnings in the nearby area continued to be in effect.
An evacuation center was set up at Hamilton High School on Mitchell Road in Anza, Cal Fire said.