A 6.4 magnitude earthquake struck Tecpan de Galeana, northwest of Acapulco on Thursday.
The temblor was downgraded from a 6.8. It hit around 10 a.m. in the southern Guerrero state about 188 miles southwest of Mexico City, and had a depth of 6.2 miles, the U.S. Geological Survey said.
There were no immediate reports of injuries or major damage.
There was only mild shaking in the resort city of Acapulco, according to an Associated Press reporter there. Nonetheless, frightened office workers streamed into the streets away from high-rise buildings, despite heavy rain that was hitting the region.
Tecpan, near the epicenter, shook ferociously, causing a “wave of panic” and some roofs to cave in, said Mayor Crisoforo Otero Heredia. But there were no injuries.
A 7.2 magnitude quake with an epicenter about 40 miles from Thursday’s quake shook central and southern Mexico on April 18.
That quake occurred along a section of the Pacific Coast known as the Guerrero Seismic Gap, a 125-mile section where tectonic plates meet and have been locked, meaning huge amounts of energy are being stored up with potentially devastating effects.
Mexico City is vulnerable to distant earthquakes because much of it site atop the muddy sediments of drained lakebeds. They jiggle like jelly when the quake waves hit.
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