Quake aftershock hits San Diego

The US-Mexico border has been rocked by a 5.7-magnitude earthquake that rattled nerves in a region still recovering from the deadly Easter tremor, seismologists said today.

The quake struck about 85 miles east of San Diego, or five miles south east of Ocotillo in California's Imperial County, the US Geological Survey said.

It was an aftershock of the 7.2-magnitude quake that shook Baja California and southern California on Easter Sunday, striking in the same zone.

Egill Hauksson, a seismologist at the California Institute of Technology in Pasadena, said: "Aftershocks can go on for months and years."

Thousands of aftershocks have occurred since the Easter earthquake. More than 100 were recorded immediately after the latest tremor, with the largest measuring 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", Mr Hauksson said.

No significant damage from Monday's quake was reported to either the San Diego County Office of Emergency Services or the Imperial County board of supervisors.

San Diego's Petco Park sports stadium swayed during the quake, causing a momentary pause at the San Diego Padres baseball game with Toronto Blue Jays. The public address announcer asked that everyone remain calm, prompting cheers from the crowd.

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

It 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.