A 4.1 magnitude earthquake shook Los Angeles Saturday -- a day after a 5.1 temblor hit the region.
No major damage or injuries are reported after both quakes.
Friday's seismic shock cut power, caused gas leaks, and knocked goods off store shelves. It also shook up fans at a Los Angeles Dodgers baseball game.
Friday's quake was centered near Brea -- about 32 kilometers south of downtown Los Angeles.
Safety crews are inspecting bridges, dams and railroad tracks for damage.
California is on the so-called Ring of Fire, which circles the Pacific Ocean. The ring has produced devastating quakes, including Japan's 2011 earthquake and tsunami.
Scientists say Los Angeles is almost certain to experience a devastating quake sometime in the next 30 years.
A 6.7 magnitude quake hit Northridge near Los Angeles in 1994, killing 60 people and causing billions of dollars in damage.