MEXICO CITY _ A powerful earthquake shook central Mexico on Tuesday, killing dozens of people, crumbling buildings and sending thousands in the capital fleeing into the streets screaming.
Authorities in central Mexican state of Morelos reported 42 deaths, and officials said at least two more occurred in the state of Mexico, which surrounds the capital.
The temblor caused buildings to sway violently in the center of Mexico City, including in the historic districts of El Centro and Roma. Mexico City Mayor Miguel Angel Mancera said some buildings collapsed, but it was too early to tell if there were casualties there.
The U.S. Geological Survey calculated the preliminary magnitude at 7.1. The epicenter was about 93 miles southeast of Mexico City in the state of Puebla.
Rescue vehicles screamed through Mexico City toward damaged buildings, and flights into the capital were rerouted to other cities.
In the upscale neighborhood of Condesa, in the heart of the city, balconies crumbled and massive cracks opened up on apartment facades. Police cordoned off entire blocks because of fears that gas leaks could cause explosions.
In Roma, buildings swayed violently, sending rubble tumbling onto cars below. A video recorded from a skyscraper showed giant plumes of dust rising in the air.
The earthquake struck on the anniversary of a 1985 temblor that killed thousands of people and devastated large parts of Mexico City _ a tragedy President Enrique Pena Nieto commemorated earlier in the day.
Mexico City is prone to major damage in earthquakes because it sits on an old lake bed that amplifies the shaking.
Susan Hough, a U.S. Geological Survey seismologist, said Tuesday's quake was likely related to one that struck off the coast of Mexico's Oaxaca state on Sept. 7, which the government calculated as a magnitude 8.2 and the USGS as an 8.1.
"An 8.1 is big enough that having an aftershock this big and this distant _ it isn't too surprising," Hough said. "It's unusual, but it fits in with the picture that we've grown to understand."
