The fast-moving vegetation fire, which has been dubbed the Canyon Fire 2, prompted 1,000 evacuations for homes in Anaheim Hills, Orange, Orange Park Acres and Tustin and triggered freeway closures in the area.
The blaze was impacting 5,000 structures, fire officials said, and no evacuees were expected to be allowed back into their homes for the rest of the night.
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The fire was first reported shortly before 10 a.m. on the eastbound 91 Freeway near the 241 interchange in Anaheim Hills. By 9 p.m., the fire scorched 6,000 acres and was 5 percent contained, Cal Fire officials confirmed in an afternoon press conference.
The blaze, which was initially estimated to be 25 acres, quickly jumped the 241 Freeway and spread into the surrounding areas, which are densely populated.
Monday night, officials confirmed 24 structures were damaged in the blaze.
VIDEO: Anaheim Hills fire chars homes near Tamarisk Drive
At least five homes were seen on fire along Canyon Heights Drive. Winds quickly pushed the flames from a ridge onto homes. The gusty conditions also blew around hot embers, causing the fire to spread from house to house.
An area resident named Adam was seen hosing down his friend's house along Canyon Heights Drive - as a house just across the street was engulfed in flames.
"We piled like 25 kids from Running Springs into our car, just got them away. Their parents came and picked them up at our house," he said.
He said he's lived in the area for years and knows how fierce the winds can get.
"It's probably going to get worse before it gets better," he said.
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Some distance away, two more homes were seen completely destroyed in a neighborhood off of Serrano Avenue and Hidden Canyon Road. One of those homes was located along E. Via El Estribo.
Two other homes -- one on Tamarisk Drive and another on a private street off of Tamarisk Drive - were also burned in the blaze.
In Orange Park Acres, a popular hiking spot along Skylark Lane was also seen filled with spot fires as firefighters fought to keep flames from entering neighborhoods in the area. Shortly before 8 p.m., when the winds died down, a large home in the 19500 block of Windes Drive was seen on AIR7 HD fully engulfed in flames.
Flames also tore across Peters Canyon Regional Park, where several residents were working to clean up the area after a fire break.
"As you walked around the corner out of the neighborhood, when this park exploded, there were 20 to 50-foot flames, and you felt it 100 yards away," said Orange resident Jeff Rice.
Within an hour, the land looked barren -- a smoky, desolate wasteland.
One thousand fire personnel were battling the aggressive flames from the ground, Steven Beach of Cal Fire said. Ten helicopters and 12 fixed-wing aircraft were fighting the fire from the sky. One firefighter was injured, possibly from smoke inhalation. The firefighter was airlifted to UCI Medical Center and was expected to be OK.
California Gov. Jerry Brown declared a state of emergency in Orange County, as well as counties in Northern California due to the fires.
The growing blaze temporarily prompted the closure of both sides of the 91 Freeway. Several lanes were back open on the eastbound side, and the westbound 91 was fully open Monday afternoon, according to Orange County CHP officials. The eastbound side of Imperial Highway, and the 241 toll lanes were also shut down in both directions.
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The Anaheim Fire and Rescue Department said the blaze quickly spread due to the winds. The area saw sustained winds of 30 mph with gusts of up to 40-45 mph. The winds were decreasing in strength in the evening, and humidity in the area was expected to increase overnight.
Beach said more resources from throughout the state are expected to join the firefight into the night, before the Santa Ana winds return early Tuesday. At the same time Tuesday morning, a red flag warning will be in effect until 10 a.m.
The blaze comes not long after another brush fire burned about 2,600 acres at the Anaheim-Corona border in late September. This was the original Canyon Fire and it prompted dozens of evacuations in Corona.
The cause of this latest fire was unknown.
If you have any questions, Anaheim Fire and Rescue provided a fire information line at (714) 765-4333. For those in Orange, a non-emergency information line is (714) 744-7495.