5.7 Mag Quake Shakes Southern California

USGS shakemap shows the earthquake epicenter east of San Diego, near the Mexico border.

SAN DIEGO -- The California-Mexico border region was rocked by a magnitude-5.7 quake Monday, rattling nerves from San Diego north to Orange County and Los Angeles.

The U.S. Geological Survey said the quake was centered five miles southeast of Ocotillo in Imperial County -- about 85 miles east of San Diego. It struck Monday at 9:26 p.m. PDT.

San Diego County Office of Emergency Services made a round of calls to all cities in the county and found no reports of significant damage. Louis Fuentes, chairman of the Imperial County board of supervisors, said he had no immediate reports of damage.

"As soon as it hit, my wife said, 'Grab the baby.' My daughter ran out to the back yard," said Fuentes, who was in his garage in Calexico, about 30 miles east of the epicenter. "It thumped really hard."

The quake was an aftershock of the deadly Easter Sunday magnitude-7.2 quake that shook Baja California and Southern California, said Egill Hauksson, a seismologist at the California Institute of Technology in Pasadena. He said the epicenter of Monday's quake occurred in the same zone of the quake in April.

"Aftershocks can go on for months and years," he said.

Thousands of aftershocks have occurred since the Easter earthquake. At least 45 aftershocks were recorded immediately following Monday's 5.7 quake, with the largest measuring at magnitude-4.5.

A 5.7-magnitude earthquake "could break windows, it could throw things on the floor, it could create cracks on the wall, but we don't expect things to collapse," Hauksson said.

Fuentes said his chandeliers swayed at his home and metal objects banged but nothing fell off the shelves. Imperial County suffered significant damage in April's Easter Sunday quake.

"All the lamps, the liquor bottles and the TV hanging from the ceiling shook, but nothing dropped," said Marina Garcia, an employee at the Burgers and Beer restaurant in El Centro, about 30 miles east of Ocotillo.

The quake was felt as a gentle rolling motion in the Los Angeles area.

San Diego's Petco Park swayed during the quake, causing a momentary pause at the Toronto Blue Jays-San Diego Padres game. The public address announcer asked that everyone remain calm. The crowd cheered.

David Eckstein of the Padres had just grounded out in the bottom of the inning when the stadium began shaking. The next batter, Chase Headley, stayed out of the batter's box for a few seconds, then stepped in.

San Diego County Sheriff's dispatch supervisor Becky Strahm said some of her colleagues reported things falling off their shelves, but there were no immediate reports of significant damage or injury.

The quake followed a series of temblors that struck Southern California over the weekend, including a pair of moderate earthquakes that rattled a desert area east of San Diego. Residents in downtown San Diego felt the ground rumbling during at least one of the Saturday quakes.