Puente Hills fault poses bigger earthquake threat than the San Andreas

A 4.4 magnitude earthquake in Los Angeles in August was along the Puente Hills fault system, a thrust fault that runs beneath one of the city's oldest and most densely populated areas.

The fault's location makes it dangerous, and it's far more active than the better-known San Andreas fault that runs through southern California.

Here & Now's Peter O'Dowd talks with seismologist Lucy Jones about the risks of the Puente Hills fault and how ready LA is for a major quake.