Strong Aftershock Rattles Southern California

More than 100 aftershocks have followed yesterday's magnitude-5.1 earthquake in southern California, including a magnitude-4.1 rumble this afternoon. The moderate earthquake yesterday forced several dozen people in one community out of their homes after firefighters discovered foundation problems that made the buildings unsafe to enter, authorities said today.

Fire crews red-tagged 20 apartment units in a building in the Orange County city of Fullerton after finding a major foundation crack. Structural woes including broken chimneys and leaning were uncovered in half a dozen single-family houses, which were also deemed unsafe to occupy until building inspectors clear the structures. The damage displaced 83 residents. Despite the evacuations, yesterday's quake, centered about 25 miles south of downtown Los Angeles, mostly frayed nerves. (More earthquake stories.)