The blaze, called the Coastal Fire, broke out Wednesday afternoon between Laguna Niguel and Laguna Beach near a water treatment plant, according to the Orange County Fire Authority, and quickly erupted in size.
At a Thursday morning press conference, fire officials said the fire had burned approximately 200 acres. An estimated containment number was not given.
While the cause of the fire remains under investigation, Southern California Edison said it sent a letter to the California Public Utilities Commission to inform them of "circuit activity" around the time the fire was reported. It's not clear if that means there was a power line down, but one resident from south Laguna Beach told Eyewitness News the power went out moments before she started hearing sirens apparently responding to the fire.
Some 900 home remained under mandatory evacuation orders, according to Assistant Fire Chief TJ McGovern.
Those orders affect homes south of Flying Cloud Drive and Pacific Island Drive to the intersection of Pacific Island Drive. Crown Valley Parkway is under a voluntary evacuation warning.
Another mandatory evacuation order was issued for the area north of the intersection of Flying Cloud Drive and Pacific Island Drive to the intersection of Highlands Avenue and Pacific Island Drive. Meanwhile, an evacuation warning issued for the Balboa Nyes (Portafina) neighborhood has since been lifted.
Fire Chief of the Orange County Fire Authority Brian Fennessy said though the structure count has not been fully determined yet, he believes about 20 homes have been destroyed.
As firefighters worked to put out major hotspots Wednesday, Fennessy said the strong winds were blowing embers into the attics, making it harder for them to get through.
"You've got to remember that this fire was wind-driven," said Fennessy during a Wednesday evening news conference. "We have embers cast very deep down into those canyons, many of them up into those palm trees. We had embers in our attic spaces, through vents. The focus is to get into these homes and to really take a look into those attics, to get down in the vegetation, to really make sure we're not leaving any hot embers in place."
McGovern said one firefighter was injured Wednesday and was taken to the hospital, but details on their condition were not released.
Meanwhile, Elaine Gennawey, the mayor of Laguna Niguel, said the city's water district has sent out an alert asking residents to reduce water usage.
An evacuation center has also been created for those seeking help.
Residents in the area can visit the Crown Valley Community Center at 29751 Crown Valley Parkway for assistance. The Orange County Emergency Operations Center has also created a public information hotline to respond to questions from residents. You can reach them at 714-628-7085.