Canyon Fire becomes one of four wildfires burning across Southern California on Thursday, forcing evacuations east of Lake Piru as crews battle flames.

The Canyon Fire is about 90 miles southeast of the massive Gifford Fire, which now covers nearly 100,000 acres. The cause is under investigation. Temperatures in the area are near 100 degrees and humidity as low as 15 percent.

A fast-spreading brush fire, known as the Canyon Fire, erupted in mountainous terrain north of Los Angeles, prompting thousands of evacuations. With 4.1 square kilometers burned in just under three hours,

The Canyon Fire around Lake Piru in Ventura County rapidly grew to 600 acres amid scorching temperatures, low humidity and gusty winds. With over 4,400 wildfires and a quarter-million acres already burned in California this year,