The U.S. Geological Survey has downgraded its estimate for the strength of today's earthquake in southern Mexico to 7.4. Initial estimates of the tremor's intensity went as high as 7.9.
The epicenter was 15 miles east of the city of Ometepec, Guerrero, according to CNN. The quake's depth was around 12.4 miles.
Aftershocks continued to rattle areas close to the epicenter more than an hour after the seismic event. Residents in cities as distant as Acapulco and Mexico City felt the initial shock.
Mexican President Felipe Calderon reported that the nation's health system was operating effectively and that he had no immediate reports of serious damage or loss of life.
"There are some broken windows," said Calderon. "Much fear. Much panic."
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