Holy Fire has scorched nearly 20,000 acres, more than 21,000 people have been evacuated.

The flames continue in southern California. Holy Fire has scorched nearly 20,000 acres this week, amid health fears over the spread of ash in the air. More than 21,000 people have been evacuated so far across the state following a series of mandatory evacuation orders. The authorities said things will only get worse, in some area. "These conditions will increase the likelihood of extreme fire behavior as well," the US Forest Service said. The wildfire continues to threaten homes around Lake Elsinore in Orange County and thousands of homes south. Officials have warned that the wildfire is still just ten percent contained. California Governor Jerry Brown has declared a state of emergency in two counties, Orange and Riverside, as schools closed yesterday for the second day in a row, due to fire warnings and unhealthy air quality. The so-called 'Holy Fire' has been raging for the past four days, with more than 1,000 firefighters that are still on the front line of the battle against the blaze. At least 10 helicopters and seven fixed-wing aircraft have been assisting fire crews. The scale of the blaze has even prompted experts from Australia and New Zealand to fly over to share their advice in battling bush fires. The man suspected of being behind the destruction, Forrest Clark, 51, appeared in court Thursday accused of arson. He made several bizarre outbursts during the hearing in Orange County, and refused to show his face. When the judge explained the process further to him, Clark said, "I do not understand though." The man accused said, "It's all a lie!" He is due back in court on August 17 for an assassination and bail review. Clark was charged with aggravated arson and criminal threats, among other offenses, in starting the Holy Fire in Cleveland National Forest. Clark allegedly sent a text to a volunteer fire chief two weeks ago saying, "The place is going to burn."