A second powerful earthquake to hit Southern California in two days hit on Friday (July 5) night - and this time it was bigger.
The 7.1 magnitude quake struck at 8:20 p.m.
(0320 GMT) local time causing damage to buildings, fires, and some injuries.
(SOUNDBITE) (English) MARK GHILARDUCCI, DIRECTOR, CALIFORNIA GOVERNOR'S OFFICE OF EMERGENCY SERVICES, SAYING: "The key though here is that this was a very large earthquake and we also know there's going to be a series of aftershocks as a result of the main quake." The epicenter was the town of Ridgecrest, also jolted by a 6.4 magnitude quake on Thursday (July 4) morning.
That, experts said, was just a foreshock to Friday's tremor.
Luckily officials have reported only minor injuries so far from Ridgecrest, although emergency services have been battling a significant number of fires, mostly caused by ruptured gas lines.
Friday's quake was also felt over a wide area with shaking reported as far south as San Diego, as far north as San Francisco and Reno, and as far east as Phoenix.
In Los Angeles, 125 miles away, pools sloshed wildly and the ground rumbled.
(SOUNDBITE) (English) STEVEN, A 53-YEAR-OLD TOURIST FROM AUSTRALIA, SAYING: "It doesn't register straight away until everything is moving and the chandelier was shaking and the kids were saying it's an earthquake." Friday's earthquake struck with eight times more force than Thursday's, and was followed by 16 aftershocks of magnitude 4 or above.
Caltech seismologist Lucy Jones said it was unlikely that this tremor would trigger other earthquakes on different fault lines.
But the USGS warns there's a 50% chance, or higher, of another magnitude 6 quake from this fault in the days ahead.