In just a few terrifying hours, the Mountain Fire became the most destructive blaze in Southern California in years. The conditions were ripe for disaster, and neighborhoods had few defenses. Here is what happened.

Now covering over 20,000 acres the blaze has grown significantly over the past day. It is so far only five percent contained and has destroyed 132 structures.

More than 130 homes have been destroyed in southern California as fire rages through Ventura County, with 10,000 residents evacuating.