A preliminary 6.0-magnitude earthquake struck near San Diego, according to the U.S. Geological Survey. The quake's epicenter was recorded 1.86 northeast of San Diego County, in Julian. It is not yet known if there are reports of injuries or damage.

Heart-melting video shows African elephants at the San Diego Zoo instinctively forming a protective circle after the earthquake hit Southern California.

A magnitude 5.2 earthquake near Julian rattled much of Southern California and Tijuana just after 10 a.m. Monday, prompting brief evacuations in downtown San Diego and shaking cities as far away as Oxnard and Palm Springs.