EL CENTRO, Calif. (AP) — An estimated 5.1-magnitude earthquake near the California-Mexico border has shaken a wide area of Southern California including San Diego.

The U.S. Geological Survey's automated seismic reporting system said the quake struck at 5:38 p.m. PDT Tuesday and was centered 18 miles west-southwest of El Centro in the state's southeastern corner.

The area has been shaking with aftershocks since a 7.2 quake that struck northern Baja California on April 4.