A magnitude 4.3 earthquake struck near Fontana in San Bernardino County Thursday, shaking parts of Los Angeles County, though no damage or injuries were immediately reported.
The quake struck around 9:30 a.m., according to the U.S. Geological Survey. Initial reports estimated the magnitude as high as 4.6 before it was officially confirmed at 4.3.
A series of earlier quakes occurred in the same area earlier in the morning, most measuring around magnitude 3.
Seismologist Dr. Lucy Jones said the region experiences frequent seismic activity, with many quakes falling in the 3.0 to 4.0 range.