A powerful earthquake has jolted Mexico City - measuring magnitude 7.1 according to the US Geological Survey (USGS) - causing buildings to sway sickeningly on the anniversary of a 1985 quake that did major damage to the capital.
The extent of damage or injuries was not immediately clear, but people fled office buildings along the central Reforma Avenue.
Mexico's seismological agency estimated its preliminary magnitude at 6.8 and said its centre was east of the city in the state of Puebla. That municipality is about 40 miles southeast of the capital.
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Pictures fell from walls and objects were shaken off of flat surfaces. Some people dove for cover under desks.
A video that appear to show the earthquake in action show lights swaying above people crowding into hallways for safety, and then those lights seeming to lose power.
Another, streamed live on Twitter's Periscope in the Federal District of the city, showed dozens of men attempting to remove large metal beams that appeared to have fallen during the earthquake. A car in the footage was covered in dust, and rubble was strewn all about.
