Wildfires roared through canyons, hillsides and residential areas in densely populated Southern California for a fourth day on Thursday as gusting winds hampered efforts to quell the flames.

Some 200,000 people have evacuated ahead of the fires, which have destroyed hundreds of homes and forced hundreds of Los Angeles-area schools to close.

Authorities feared the four major fires — ranging from Los Angeles up the Pacific coast to Santa Barbara County — would be whipped up by the region's notorious westward Santa Ana winds that could reach hurricane strength.