A powerful earthquake shook south and central Mexico on Friday, causing people to flee buildings and office towers in the country's capital.

Crowds of people streamed out on to the streets of Mexico City as the ground shook as well as on streets in Oaxaca state's capital, nearer the quake's epicenter.

"It was awful," said Mercedes Rojas Huerta, 57, who was sitting on a bench outside her home in Mexico City's trendy Condesa district, too frightened to go back inside. "It started to shake; the cars were going here and there. What do I do?"

She said she was still scared thinking of the September 19 earthquake that left 228 people dead in the capital and 369 across the region. Many buildings in Mexico City are still damaged from that quake.

The U.S. Geological Survey put the quake's preliminary magnitude at 7.2 and said its epicenter was 33 miles northeast of Pinotepa in Oaxaca state. It had a depth of 15 miles.