The Canyon Fire is burning through steep terrain near the Ventura-Los Angeles county line, prompting evacuations and air quality warnings.

Firefighters Friday were trying to make progress after the Canyon fire exploded to nearly 5,000 acres, forcing residents in northern Los Angeles and Ventura counties to evacuate.

Fire crews from Ventura and Los Angeles counties are battling a rapidly growing vegetation fire in Holser Canyon, near Lake Piru, in 100-degree heat. The blaze, called the Canyon Fire, is estimated to be at 1,