A nearly 40,000-acre wildfire forced people from their homes in two Southern California counties over the weekend as firefighters worked to contain the blaze in challenging terrain.

The Gifford fire, which has been fueled by dry conditions and warm weather, has spread to two counties, officials said.

The Gifford fire has rapidly spread after firefighters contained the Madre fire. Together, the two blazes have already burned over 100,000 acres.