A preliminary magnitude-4.3 earthquake in the San Bernardino area produced shaking that was felt over widespread parts of Southern California.
The quake, reported at about 9:30 a.m., was one of four of magnitude-2.5 or greater in the area, which includes the communities of Muscoy and Rialto.
The first quake was reported at 8:34 a.m. in the San Bernardino County community about 50 miles east of Los Angeles. Shaking was reported in Riverside, San Bernardino and other inland areas.
The second stronger quake was reported at about 9:30 a.m. Shaking was reported in Los Angeles, Santa Monica, Torrance, Long Beach, Pasadena and other areas.
A magnitude-3.1 aftershock was reported about four minutes later.
Several smaller earthquakes have been reported Thursday morning before and after the largest quake.
The area has seen about 130 quakes of magnitude 3.0 and greater since 1990, many coming in clusters. There have been eight quakes of magnitude-4.0 since that time.
Jonathan Lloyd, NBC Los Angeles