A major earthquake rattled Southern California on Monday morning. Initial reports had the quake measuring 6.0 magnitude, but the USGS quickly downgraded the temblor to 5.2. The quake struck at 10:08 a.

A moderately strong, 5.2-magnitude earthquake struck in Southern California on Monday, according to the United States Geological Survey. The temblor happened at 10:08 a.m. Pacific time about 2 miles south of Julian, Calif., data from the agency shows. U.S.G.S. data earlier reported that the magnitude was 6.

An earthquake measuring 5.2 magnitude struck the interior of San Diego County in California on Monday, the U.S. Geological Survey said.