MEXICO, Sept 7 (Reuters) - An earthquake of magnitude 8 struck off the southern coast of Mexico late on Thursday, the U.S. Geological Survey (USGS) said, shaking buildings in the capital city.

People in Mexico City ran out into the streets after the quake struck, a Reuters witness said.

Its epicentre was 123 km (76 miles) southwest of the town of Pijijiapan, at a depth of 33 km (21 miles). Widespread, hazardous tsunami waves were possible, the Pacific Tsunami Warning Centre said. (Writing by Robert Birsel; Editing by Clarence Fernandez)

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