Orange County Fire Authority crews responded to the 29400 block of Silverado Canyon Road at about 10:15 p.m. Wednesday and attacked the blaze from the ground and air.
Amid elevated fire danger due to strong winds, officials estimated the blaze grew to 7,200 acres, but the OCFA later downgraded acreage to 6,400 due to more accurate mapping. Containment is at 10%.
The ferocious winds that hampered efforts during the early morning hours Thursday died down at night, enabling firefighters to make progress, although hot spots were still flaring up on the Silverado Canyon hillsides.
A U.S. Forest Service spokesperson told Eyewitness News the firefighters injured, who had to be airlifted, are in the hospital recovering from non-life threatening injuries.
The Bond Fire forced mandatory evacuations for residents in the Silverado Canyon and Williams Canyon areas as it continued to grow at a rapid rate of speed. Modjeska Canyon is also under mandatory evacuation orders, and residents in the area of Borrego Canyon and other nearby communities were also warned to prepare to evacuate.
BOND FIRE MAP: See areas under mandatory, voluntary evacuation orders
Residents of Foothill Ranch and Portola Hills west of El Toro and north of the 241 toll road were also placed under mandatory evacuation orders. Remaining parts of Portola Hills remained under voluntary evacuation warnings, officials said.
The Orange County Sheriff's Department says 25,000 residents are under mandatory evacuation.
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Fire officials urged those under evacuations to heed the orders. The Red Cross established a temporary evacuation center at Santiago Canyon College, Lot 2, located at 8045 E. Chapman Avenue.
Residents in the Lake Forest area are also under voluntary evacuation orders. The order applies to homes from the 241 toll road along Bake Parkway to Musick north to the Irvine border, and from the 241 north to Bake to Foothill Ranch Community Park.
However, OCFA later lifted evacuation orders for the Lake Forest area, north of Alton Parkway, east of the 241.
Fire helicopters and a helitanker responded to the scene as the flames engulfed the home that sparked the vegetation fire.
The overnight fight against the flames posed difficulty for crews, who said the fire is "growing rapidly" in a southwest direction.
The blaze also prompted the closure of Sand Canyon Road, from Jackson Ranch to the 241 toll road, according to OCFA. By the evening, OCFA said Caltrans reopened all roads except for Santiago Canyon Road.
There is no confirmation about what caused the initial flames. However, rumors are flying among evacuees about the source.
"A lot of people have been getting generators because the power companies cut our power during the winds, so people have been getting generators out there, and there's a lot of people that probably have never had a generator before. It possibly was started from the generator into the brush," one resident said.
Residents who didn't evacuate were left without power and cell service.
Elevated fire danger continues in Southern California as Santa Ana winds combine with dry conditions and warm temperatures.
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