SAN DIEGO (CNS) - A magnitude-5.4 earthquake rocked the San Diego area late this afternoon, giving homes, high-rises, businesses and roadways throughout the county a pronounced shaking but apparently causing no injuries or property damage.

The temblor, centered about 15 miles north-northwest of Borrego Springs, struck at 4:53 p.m., according to the U.S. Geological Survey.

Though the quake was widely felt across the county, the region’s police and emergency-services agencies received no immediate reports of any problems resulting from the temblor.

Darren Pudgil, spokesman for San Diego Mayor Jerry Sanders, said there had been no reports of damage, though the quake temporarily knocked out elevator service at City Hall, forcing many workers to use the stairs to exit the 13-story building.

USGS seismologist Kate Hutton told reporters at Caltech in Pasadena that the quake likely occurred in the San Jacinto fault zone, and it was followed by about two dozen small aftershocks, the largest a magnitude-3.6.

She said the quake was likely not an aftershock to the magnitude-7.2 temblor centered near the Mexican border that rattled much of Southern California in early April.

“This earthquake, probably, although it’s pretty close in time after the April earthquake, it’s probably not an aftershock because it’s located in a different location,” Hutton said. “But it probably is what we would call a triggered earthquake, because we’re now thinking that the 7.2 earthquake in April changed the strain slightly in the San Jacinto fault area and the Elsinore fault area, and it increased the number of small earthquakes that were happening there. And this is an example of an earthquake that’s like that.”

The shaker also jostled communities in the Riverside area and as far away as Palmdale in northern Los Angeles County.

Gil Alexander, a spokesman for Southern California Edison, said the shaking was felt at the San Onofre Nuclear Generating Station, but was “not sufficient to lead to an automatic shutdown of the reactor.’ Inspectors looking over the facility had found “no indication of damage,’ Alexander
added.

At Palm Canyon Resort in Borrego Springs, cooking pans, glasses and other objects fell from shelves as the buildings rocked back and forth, but nothing broke, said Scott Elliott, the establishment’s manager.

“It was a strong hit,’ he said. “You could hear it coming - a loud rumbling, like a truck.’

Celina Deldadillo, a waitress at nearby Kendall’s Cafe, said she was about to leave her home to go to work when the temblor hit, startling her so much that she screamed.

“It was scary,’ she said by telephone from her Palm Canyon Drive workplace, where boxes of cereal and other supplies fell to the floor as the building vibrated.

Deldadillo added that the quake was the strongest she’d ever felt.

“I know a lot of people are shaking now, like me,’ she said. “My heart’s going, `boom, boom boom!’’

Hutton said residents should take today’s quake as a warning to be
prepared for temblors.

“The best way for people to look at this earthquake is that it’s a
drill,’ she said. “... If this one had been the big one, what would I have
done? Would I have been prepared? Would I have had my supplies, my plan and all that? ... So review everything, check your kit, because we can’t predict
earthquakes, we don’t know when they’re going to happen, so we have to be
prepared all the time.’