The earthquake was initially reported as being of 7.4 magnitude.
The quake’s epicenter was 8 kilometers southeast of Atencingo in the Mexican state of Puebla at a depth of 51 kilometers, USGS said.
Thousands of people took to the streets Tuesday, fleeing their shaking houses, an eyewitness told Reuters.
There have been no reports of casualties or destruction as a result of the quake so far.
The Tuesday’s quake hit just hours after many in the country took part in earthquake drills, held on the anniversary of the devastating 1985 quake, which killed more than 5,000 people in Mexico City.