Southern California earthquakes deemed April aftershocks

The southern California earthquakes Monday night peaked at magnitude 5.7, disrupting a San Diego Padres baseball game, but no significant damage or injuries have been reported.

A southern California earthquake of magnitude 5.7 struck at 9:26 p.m. PDT Monday night, centered five miles southeast of Ocotillo in San Diego County, about 85 miles east of San Diego. It could be felt throughout the Los Angeles County area, the Los Angeles Times reported.

Twitter users sent in photos of spilled merchandise in grocery stores and the Blue Jays-Padres game was halted briefly, but otherwise there were no reports of serious injury or significant damage according to the Associated Press. As the lights and poles at Petco Park swayed back and forth, this exchange could be heard by announcers:

“We are experiencing a tremor right now, an earthquake here in the ballpark in San Diego, and it’s very significant,” said one announcer.

“Ahhh, it’s just a tremor,” joked another.

“I can hear the fans’ reaction,” said the first, as the camera panned around the stadium to smiling faces and some children making waving gestures. “They’re used to this,” the announcer said as the crowd cheered.

The center of Monday's quake was in the same zone as an April earthquake, California Institute of Technology seismologist Egill Hauksson told the AP.

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

More than 100 smaller aftershocks were recorded after the quake, with the largest registering a magnitude 4.5. Thomas Jordan, director of the Southern California Earthquake Center at the University of Southern California, told the Los Angeles Times that the fault where the April quake struck has been very active recently. "It's been especially rich at the north end of the fault," he said, adding that he did not find Monday's swarm of quakes that unusual.

KTLA Fox news reported the temblor as 5.9 at 9:34, and updated its report at 9:50 p.m. as coming from the general area where a 7.2 magnitude earthquake hit Mexico’s Baja peninsula, killing at least one person and causing significant damage.

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," said Mr. Hauksson.

There were no reports of significant damage, according to officials in San Diego and Imperial counties.

"As soon as it hit, my wife said, 'Grab the baby.' My daughter ran out to the backyard," Louis Fuentes, chairman of the Imperial County Board of Supervisors, told the AP. He had been in his garage in Calexico, 30 miles east of the epicenter. "It thumped really hard."

Fuentes and others in the area said objects shook and swayed but nothing fell.

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

Related:

• Why Mexico earthquake, stronger than Haiti's, did much less damage
• Baja earthquake: 'Power lines were crashing against buildings'
• Mexicali earthquake: Damage could have been much worse