5.2-Magnitude Earthquake Rattles Southern California, Felt in Los Angeles, San Diego

— -- An earthquake with a preliminary magnitude of 5.2 shook Southern California early this morning.

The quake was centered about 14 miles northwest of Borrego Springs -- about 90 miles east of San Diego -- and hit just after 1 a.m., according to the U.S. Geological Survey.

Residents reported feeling shaking from the earthquake in San Diego, West Los Angeles, Riverside and Woodland Hills, ABC Los Angeles station KABC reported.

There were no immediate reports of injuries or property damage, San Diego Sheriff's Office Lt. Andrea Arreola said.

"At this point, we are just monitoring," the area, she said.

Officials said the earthquake set off a lot of alarms at businesses.

The earthquake occurred along the San Jacinto Fault, historically the most active fault in Southern California, according to seismologist Lucy Jones.

Within an hour, there were six aftershocks in the same general area, the strongest a 3.5-magniude tremor at 1:06 a.m. with roughly the same epicenter, but at a depth of 6.7 miles.