A brush fire threatening structures near the 241 toll road in Orange County Monday prompted authorities to evacuate the campgrounds at Irvine Lake.
Authorities received a report at 10:45 a.m. of a vegetation fire near the northbound 241 just south of Santiago Canyon Road, and the fire grew quickly from there, according to Orange County Fire Authority Capt. Steve Concialdi.
By mid-day, the 241 Fire had grown to 150 acres, burned two abandoned outbuildings and threatened about 15 more structures around the Irvine Lake area, Concialdi told KPCC. By late afternoon it had grown to 180 acres, and was about 50 percent contained.
"Even though we have light wind out here, the vegetation is extremely dry due to the fourth year of a pretty significant drought," Concialdi said.
The Orange County Sheriff's Department said via Twitter it assisted with the evacuation of up to 15 people.
Everyone at the campgrounds was brought to a safe refuge area by the sheriff's department and the California Highway Patrol, Concialdi said.
Santiago Canyon Road was closed between the 241 and Modjeska Canyon, according to the Orange County Emergency Operations Center.
With rising temperatures and extremely dry vegetation, firefighters were facing a "long, hard-fought battle," Concialdi said.
Five helicopters and three air tankers were providing support for fire crews on the ground.
Concialdi said this was just the start of a very active fire season.
"We're going to see this throughout the year just because it's so dry and the vegetation is at an extremely tinderbox condition," he said.
This story has been updated.