MEXICALI, Mexico - Aftershocks rattled the southwest Mexico-U.S. border on Monday morning in the aftermath of a major earthquake that killed two people, blacked out cities and forced the evacuation of hospitals and nursing homes.

The human toll was minimal in large part because the energy from the quake moved northwest of Mexicali toward a less populated area, said Jessica Sigala, a geophysicist from the U.S. Geological Survey.

Sunday afternoon's earthquake hit hardest in Mexicali, a bustling commerce center along Mexico's border with California, where one man was killed when his home collapsed just outside town and another died when he ran into the street in panic and was struck by a car.

Shattered glass

Across the border in Calexico, the quake damaged nearly 80 percent of the city's historic downtown area, authorities said. Three tanks holding the city's water supply were damaged, City Manager Victor Carrillo said.

City officials asked residents to limit water use to essential bathing, cooking and washing. .

The Imperial County fire chief said one person was critically injured by Sunday's earthquake and remains hospitalized in El Centro. No further details were available.

Dozens of aftershocks jolt ‘lucky’ Calif., Mexico - Expert: Energy from major earthquake moved toward less populated

Submitted by Quest-News-Serv... on Tue, 04/06/2010 - 03:42.

Expert: Energy from major earthquake moved toward less populated area

Dozens of aftershocks jolt ‘lucky’ Calif., Mexico

Expert: Energy from major earthquake moved toward less populated area

Officials inspect damage in Calexico, Calif.

Fred Greaves / Reuters

A police officer and U.S. border patrol agent inspect the damage to a building in downtown Calexico, Calif., following Sunday's 7.2-magnitude earthquake. Officials declared a state of emergency in the city.

View related photos

var hasRelatedPhotos = 'true';if (hasRelatedPhotos=='true'){var vRPL = document.getElementById("viewRelatedPhotosLink");if (vRPL!=undefined) vRPL.style.display = "";var vLRPG = document.getElementById("linkRelatedPhotos");var vLIRPG = document.getElementById("linkImgRelatedPhotos");if (vLRPG) {if(vLIRPG) vLIRPG.href=vLRPG.href;}}

getCSS("3088867")

Video

Aftershocks continue across Mexicali

April 5: Building inspectors declare 80 percent of buildings in downtown Calexico, Calif. unsafe to enter. NBC's George Lewis reports.

Nightly News

Scientists measured about 100 aftershocks early Monday morning, said seismologist Kate Hutton at the California Institute of Technology in Pasadena.

They caused no new damages in Mexicali, said Alan Sandoval, a civil protection inspector.

At least 100 people were injured in Mexicali, most of them struck by falling objects. Power was out in virtually the entire city and the blackout was expected to last well into Monday, Escobedo said.

All 300 patients were evacuated from the Mexicali General Hospital because of the structural damage to the building, which also was without electricity and water. Some patients were taken to private clinics but others were in tents.

It was unclear how long the emergency generators powering the private clinics could last. Sandoval said the most critical patients would be transported to hospitals in Tijuana and the coastal town of Ensenada.

Sandoval said the Easter holiday delayed damage assessments for Mexicali, as did landslides that slowed traffic on the toll road into the city.

Scientists said the main earthquake probably occurred on a fault that has not produced a major temblor in over a century. Preliminary data suggest the quake occurred on the Laguna Salada fault, which last unleashed a similar-sized quake in 1892. Since then, it has sparked some magnitude-5 temblors.

U.S. Geological Survey seismologist Erik Pounders described the area as a "chaotic" system of faults that needed more research.

In Calexico, California, a city of 27,000 right across the border from Mexicali, the city council declared a state of emergency.

Calexico police Lt. Gonzalo Gerardo said most of the damage occurred downtown, where buildings constructed in the 1930s and '40s were not retrofitted for an earthquake of this magnitude.

"You've got a lot of cracks. You've got a lot of broken glass," he said. "It's unsafe for people to go there."

Rosendo Garcia, 44, was driving his daughter home from work when the quake struck.

"It felt like I was in a canoe in the middle of the ocean," he said, adding that homes in his trailer park were seriously damaged, including one knocked off its foundation.