MEXICO CITY — A powerful earthquake in southern Mexico shook buildings in this megacity Tuesday, sending objects tumbling from shelves, cracking walls and emptying buildings of millions of frightened residents fleeing to the streets.
But there were no reports of fatalities and only seven people were injured nationwide in what officials said was the strongest quake to hit this city since a 1985 temblor killed as many as 10,000 people.
Six aftershocks rocked the capital.
The quake hit at 12:02 p.m. local time (2:02 p.m. EDT) and lasted for more than a minute. Communication networks were jammed in the quakes immediate aftermath. Utility lines fell to the ground in much of central Mexico City.
President Felipe Calderon, traveling in Monterrey in northern Mexico, said, Fortunately, there are no reports of serious damage."
The hospitals and clinics are operating normally, with some broken glass, a big fright, some panic, it is true. But they are all right, Calderon said.
There was some confusion on where the quake had taken place. The U.S. Geological Survey, which said the quake measured 7.4 on the Richter scale and happened 12 miles underground, placed the epicenter in Oaxaca state, 200 miles southeast of the capital. Mexican seismological authorities reported, however, that the epicenter was a bit further north, in Ocotepec in Guerrero State, home to the Pacific resort of Acapulco.
Damage appeared to have been greater nearer the epicenter. The governor of Guerrero state said 800 houses had been affected by the quake, the official Notimex news agency reported, and five people were injured in Oaxaca, according to Laura Gurza, the chief of Mexico's civil defense system. Two people were injured in Mexico City, she added.
Because the quake took place under land, there was no threat of a tsunami.
In addition to the capital, jolts from the temblor were felt in the states of Oaxaca, Michoacan, Tabasco, Veracruz, Puebla, Guerrero and the state of Mexico.
The lack of fatalities seemed miraculous. A pedestrian overpass fell on a small bus in Azcapotzalco, a northwestern borough of Mexico City, but caused no injuries. An electrical transformer plunged from a pole, crushing a taxi, also without injuries.
Pedestrians in the historic part of Mexico City watched in awe as dust rose from a shaking building that many felt was certain to collapse. When the ground stopped rolling, however, the building still stood.
Local radio stations said that some people were injured as they evacuated buildings. Television networks showed images of legislators running out of Congress in mid-session.
The noontime quake struck as most Mexico City residents were at their desks, toiling in factories, tending shops or in their homes.
Mexico City Mayor Marcelo Ebrard said cracks opened in walls, and buildings subject to tilting leaned further. Power went off in many districts, but there were no cuts to water or other strategic services, he said.
Right now, we dont have major damage, that is to say collapsed buildings, Ebrard said, noting that disaster personnel had flown over the city to assess the damage.
"It was really strong," said Sergio Cuevas, a graphic designer who was in his third floor office. "It lasted for a really long time."
The peal of police sirens sounded across the city as people milled on sidewalks, scurrying for safety amid each aftershock. With many traffic signals out, traffic was snarled.
"It seemed like forever to get out of the building because plaster was falling," said Larry Fisher, an American retiree living in Mexico City's La Condesa neighborhood.
"I went back up, and all the plaster had come down. It's just a disaster. Cracks all over the house," Fisher said.
His wife, Ana Frank Fisher, said evacuating the 10-story building during the tremor was difficult. "It was hard to keep your balance. I was holding onto the handrail," she said.
Mexico Citys international airport continued to operate normally, turning back only one flight from Houston, according to Milenio television.
In Oaxaca, the state where the quake was strongest, buildings shook fiercely but damage was limited.
It was felt in the whole state, Oaxaca Gov. Gabino Cue said. We have some cracks in hospitals and schools. ... We dont have any deaths for the moment.
Tuesdays quake evoked memories of the one in 1985, which was measured at 8.0. Thousands who had yet to leave their homes for work when that quake struck shortly after 7 a.m. died when their apartment complexes collapsed.
Alberto Serur, a tax auditor, said Tuesday's shaking was almost as bad as 1985.
Eighty-five was like this, he said, moving his hand up and down jerkily. This time, it was like this, he added, moving his hand sideways.
He took a phone call as a cellular signal returned to the area, then reported back. They felt it really strongly in Puebla, too, he said, referring to a city southeast of the capital.
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