Mexico City earthquake latest: Huge tremors 'kill at least 49' as buildings collapse

Officials say that they're not sure how many people are trapped in various buildings that caught fire around the city

An injured woman is pictured in Mexico City after a 7.1 magnitude earthquake (RONALDO SCHEMIDT/AFP/Getty Images)

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 quake caused rubble to fall onto cars, and some building facades to collapse to the streets.

The extent of damage or injuries was not immediately clear, but people fled office buildings along the central Reforma Avenue. Local media reported at least 49 deaths, and an unspecified number of others who may be trapped in buildings throughout the city.

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.

One visitor to the city, who asked to be identified simply as Juan, was in a penthouse building in the city when the quake struck. He sent The Independent a text which said: "One word: apocalyptic. We heard the earth roar and the buildings creak. My heart was still pounding fast, minutes afterwards."

Pictures fell from walls and objects were shaken off of flat surfaces. Some people dove for cover under desks.

A video that appears to show the earthquake in action shows lights swaying above people crowding into hallways for safety, and then those lights seeming to lose power.

Another video, 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 - it was not clear what was underneat. A car in the footage was covered in dust, another was smashed, and rubble was strewn all about.

Mexican minister to China Jorge Guajardo tweeted a video showing a building that had collapsed, with rubble covering the sidewalk below. "Panic and frustration after Mexico City earthquake," Mr Guajardo wrote alongside the video.

Yet another posted by Mr Guajardo showed the facade of a what appears to be a 10 story building losing its facade.

The earthquake hits less than two weeks after a devastating 8.1 magnitude trembler that impacted off the coast of Chiapas. That event killed at least 98 people, and left devastation primarily in the souther Mexican states of Chiapas and Oaxaca. All told, those two states have a combined population of nine million people, and are impoverished.

The USGS estimated that there were at least six aftershocks exceeding a 5.0 magnitude after that quake earlier this month. An estimated 1.85 million homes lost power after the initial shock wave, but 74 per cent of those homes saw services restored within hours. The earthquake was the most powerful that Mexico has seen in at least a century.

Tuesday's earthquake also came on the anniversary of the 1985 earthquake in Mexico City. That quake, an 8.0 magnitude tremor, struck early in the morning and killed at least 5,000 people.