Amid red-flag conditions brought on by gusting winds and dangerously low humidity, a wildfire raced across terrain in the Santiago Canyon area, forcing mandatory evacuations in the Orchard Hills area, threatening structures and blocking key roadways through the region.

The blaze erupted at 6:47 a.m. in the area of Santiago Canyon and Silverado Canyon roads., and within an hour it had scorched roughly 50 acres. The fire was estimated at about 200 acres by 9:30 a.m.

Mandatory evacuation orders were issued for the Orchard Hills community north of Irvine Boulevard from Bake Parkway to Jamboree Road. Irvine police said the University Community Center at 1 Beech Tree Lane and the Quail Hill Community Center at 35 Shady Canyon Drive were both available as evacuation centers.

The evacuation order affected roughly 60,000 people, according to the Orange County Fire Authority.

Although structures were reported to be threatened and there were some reports of buildings already burned, fire authorities had not yet confirmed any structural damage. There were no reports of any injuries.

The Foothill Transportation Corridor (241) Toll Road was closed from Santiago Canyon Road to the Eastern Transportation Corridor (133) Toll Road.

Southbound state Route 91 was also closed in the area north of the 241 Freeway.

Orange County Fire Authority officials said the flames had jumped the 241 Freeway shortly after 9 a.m.

The fire was sending a major plume of smoke over the entire region, creating unhealthy air across a wide area. The Orange County Health Care Agency urged residents in affected areas to stay indoors, limit outdoor activity, keep windows and doors closed and run air conditions to filter the air.

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