TRABUCO CANYON, CA — Orange County firefighters are battling a fast-moving fire in steep terrain in the Trabuco Canyon area. Crews are on the scene in Holy Jim Canyon where about 4,000 acres of brush burnt in just about six hours. The Canyon is under evacuation.

The fire broke out shortly after 1 p.m. and quickly spread fueled by dry, dense brush that hasn't burned in decades. As of about 8:15 p.m., the fire had scorched around 4,000 acres and zero containment with a "moderate rate of spread," rolling downhill toward the Main Divide forest road, within sight of south Corona, El Cerrito and Glen Ivy Hot Springs, according to the U.S. Forest Service. Black smoke from the blaze can be seen across much of Orange and Riverside counties. The blaze destroyed one cabin, and fire officials are calling on people in the Holy Jim area to evacuate. No evacuation center was immediately established. The fire, dubbed the Holy Fire broke out in the area near Holy Jim Canyon and Trabuco Creek roads. About 600 firefighters were deployed as temperatures hovered around 100, even at the higher elevations. Two firefighters reported heat-related injuries, and they are expected to recover. Crews from Orange County, Riverside County and Cal Fire were working through the dense vegetation to attempt to get a line around the blaze, but there was no likelihood of containment overnight or even Tuesday, according to reports from the scene.

The fire quickly engulfed one cabin, according to the Orange County Fire Authority's Steve Concialdi. It's burning in an area known for remote cabins amid challenging terrain. Orange County sheriff and fire authority helicopters are conducting water drops along with air tankers. The fire is burning in the Cleveland National Forest toward Riversde County, and the US Forest Service is taking the lead in battling the blaze, according to Orange County officials. (Get Patch real-time email alerts for the latest news from your California neighborhood. Also, download the free Patch iPhone app or free Patch Android app. Also, be sure to follow your local Patch on Facebook!)

Precautionary evacuation orders were issued for the sparsely populated Holy Jim community and Trabuco Canyon area, home to dozens of weekend cabins. All campgrounds in the Trabuco Ranger District were closed and forest road closures were in effect for Trabuco Creek, Maple Springs, North Main Divide, Bedford and Indian Truck Trail. Also, Blue Jay Campground and El Cariso Campground off Highway 74 were evacuated. The American Red Cross has set up an evacuation center at Rancho Santa Margarita Bell Tower Regional Community Center at 22232 El Paseo for those affected by the fire.

"There probably aren't too many people back there," said said Jeanna Smith of the Cleveland National Forest.

The OCFA said residents in the Holy Jim area can call the Public Information Hotline at (714) 628-7085.

Roughly a dozen water-dropping aircraft were being used to help control the blaze. Orange County Fire Authority Capt. Tony Bommarito said the area probably hasn't burned since about 1980.