A preliminary magnitude 4.2 earthquake shook an area about an hour outside San Diego Wednesday and was followed by a magnitude 3.0 aftershock, according to the USGS.

WATCH LIVE: ABC7’s Quake Cam is up after an earthquake rattles area near San Diego

A 4.2 magnitude earthquake struck near Julian, Calif. in San Diego County on Wednesday, Dec. 6, 2017. (USGS)

The quake was centered about 13 km northeast of Julian, California, which is located a little more than an hour’s drive from San Diego.

The earthquake registered on ABC7’s Quake Cam. There was no immediate word on injuries or damage.