A brush fire sent thick smoke over part of Orange Countyinto the evening Monday, forcing campground evacuations and a road closure.
Fifteen homes were also evacuated as a precaution.
Three abandoned Irvine Ranch houses were destroyed by the fire.
Santiago Canyon Road was closed between Highway 241 Modjeska Canyon Road. Authorities evacuated Irvine Lake Campground, about 10 miles northeast of Irvine, around noon.
A firefighting air tanker was deployed to battle the fire.
About 10 to 15 people were evacuated, said Steve Concialdi, of the Orange County Fire Authority. The fire burned an estimate 250 acres by noon, he said.
"Because of the dry, tinder-like vegetation, that does quickly grow," Concialdi said. "We're only in July. We're going to have an extremely active fire season. Have a plan, be ready."
Before 6 p.m., some residents were being allowed to return to their homes.
A fire burned in the same area earlier this month.
More than 3,380 wildfires have been reported since the start of the year in California, according to Cal Fire. The agency reported 2,491 fires during the same period last year.
California averages about 2,250 through the six months of the year.
At midday, another brush fire burned an estimated 5 acres near Moreno Valley. The fire closed one lane on the eastbound 60 Freeway west of Jack Rabbit Trail between Beaumont and Moreno Valley.
Mekahlo Medina contributed to this report.