Much-needed rain has begun to fall over Southern California, bringing relief to the drought-stricken region but also the threat of toxic runoff.

Officials cautioned that ash in recent burn zones was a toxic mix of incinerated cars, electronics, batteries, building materials, paints, furniture and other household items.

Southern California is expecting up to an inch of rain in some parts, aiding the fight against wildfires but also causing landslides that threaten homes in Los Angeles area. NBC News' Steve Patterson reports on the anxieties residents face as they try to resettle.