The Holy fire in the Cleveland National Forest pushed closer to some Riverside County homes Wednesday, prompting a new round of mandatory evacuations as authorities arrested a man suspected of igniting the blaze.

The fire, which has burned 6,200 acres, forced evacuations in McVicker Canyon, Rice Canyon, Horsethief Canyon, El Cariso, Rancho Capistrano, Indian Canyon, Glen Eden, Sycamore Creek and Mayhew Canyon, according to the U.S. Forest Service. The Ortega Highway corridor from Lookout Roadhouse to Nichols Institute was also included in the evacuation order.

Forrest Gordon Clark, 51, was arrested on suspicion of two counts of felony arson, one count of felony threat to terrorize and one count of misdemeanor resisting arrest in connection with the ignition of the Holy fire.

It was not immediately clear how the fire was set. Clark was booked Wednesday and was being held on $1-million bond.

Susan Schroeder, spokeswoman for the Orange County district attorney’s office, said it would file criminal charges against Clark.

“We expect to bring him to justice for these terrible crimes,” she said.

Clark is slated to appear in court Thursday, records show.

The Holy fire, which was 5% contained and burning toward Horsethief Canyon and McVicker Drainage, broke out Monday and has destroyed 12 structures.

The fire’s growth came on another day of record high temperatures in parts of Southern California. Los Angeles International Airport hit a new high for the day at 94 degrees. UCLA, Camarillo and Escondido also hit new highs, while Santa Ana and Newport Beach tied their daily records.

Expected higher humidity and cooler temperatures could aid firefighters as they build containment lines around the blaze, which has ripped through chaparral and brush.

Eighteen wildfires that continue to burn across the state have scorched more than 644,000 acres, an area about the size of Sacramento County. The largest is the Mendocino Complex — made up of the Ranch and River fires — which has burned more than 300,000 acres and is the biggest fire ever recorded in California. It was 47% contained as of Wednesday evening.

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