UPDATE: At least 200 people have been killed, according to a report issued by the governor.
On the 32nd anniversary of one of the worst earthquakes to ever hit Mexico, a 7.1 magnitude quake struck the city. Back in 1985, the earthquake was a powerful 8.0 magnitude.
For several weeks, Mexico City ran drills to prep for another major earthquake. It is unclear the extent of damages and injuries.
Mexico's seismological agency set the magnitude at 6.8 and said its center was east of the city in the state of Puebla.
With Mexico City being built on a lake bed, it makes the area more susceptible to quakes.
According to the USGS, located atop three of the large tectonic plates, Mexico is one of the world's most seismically active regions. The relative motion of these crustal plates causes frequent earthquakes and occasional volcanic eruptions.
Most of the Mexican landmass is on the westward moving North American plate. The Pacific Ocean floor south of Mexico is being carried northeastward by the underlying Cocos plate. Because oceanic crust is relatively dense, when the Pacific Ocean floor encounters the lighter continental crust of the Mexican landmass, the ocean floor is subducted beneath the North American plate creating the deep Middle American trench along Mexico's southern coast.