An earthquake has shaken California's border with Mexico.
Preliminary information from the California Integrated Seismic Network says the 10:48 a.m. (1748 GMT) Wednesday quake was magnitude 5.9 and was centered about 100 miles (160 kilometers) east of San Diego, about 20 miles (30 kilometers) southeast of the Mexican city of Mexicali.
Buildings briefly swayed in San Diego.
San Diego County sheriff's Lt. Anthony Ray says there have been no reports of damage or injury.
The automated seismic network reported a magnitude-4.9 aftershock at 10:53 a.m.