At least 149 people have been reported dead after a devastating earthquake shook Mexico City and the surrounding areas, destroying buildings and sending residents scrambling to help anybody caught under rubble.

The steadily rising death toll made it the second deadliest earthquake to hit Mexico since a 1985 catastrophe that killed thousands. Videos and images showed rubble covering streets, cars smashed by fallen debris, and groups of people working together to lift large metal beams that appeared to have fallen during the trembling.

The powerful earthquake registered with as 7.1 magnitude tremor, according to the US Geological Survey (USGS), and occurred on the anniversary of the cataclysmic 1985 quake that ravaged Mexico City and left thousands dead. Earthquake drills were reportedly planned for the day. Mexico's seismological survey pegged the preliminary magnitude just a bit smaller, at 6.8, and indicated that the epicentre was located in the nearby municipality of Puebla. That community 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."

Fatalities were climbing in the country's capital of Mexico City, where Mayor Miguel Angel Mancera said at least 30 people had died and structural damage was widespread. The streets were strewn with dust and rubble from at least 44 collapsed buildings. Mr Mancera offered a glimmer of hopefulness, saying 50 to 60 people had been pulled alive from the detritus.

Officials in the central Mexican state of Morelos said that there were at least 54 people killed as a result of the earthquake in his state, with 12 of those deaths occurring in the city Jojutla and four more in the state capital of Cuernavaca. Nine deaths were reported by Governor Del Mazo of the State of Mexico, a revision from the initial two deaths that were reported in that state. At least another 26 deaths were reported in Puebla.

Mexico City earthquake in pictures Show all 13 1 /13 Mexico City earthquake in pictures Mexico City earthquake in pictures A handout picture provided by the citizen Edgar Cabalceta shows a general view of Mexico City following a magnitude 7.1 earthquake, in Mexico City, Mexico EPA Mexico City earthquake in pictures Rescuers and residents look for victims amid the ruins of a building knocked down by a magnitude 7.1 earthquake that jolted central Mexico damaging buildings, knocking out power and causing alarm throughout the capital on September 19, 2017 in Mexico City, Mexico. The earthquake comes 32 years after a magnitude-8.0 earthquake hit on September 19, 1985 Getty Images Mexico City earthquake in pictures A police officer stands guard near a building which collapsed after a quake rattled Mexico City RONALDO SCHEMIDT/AFP/Getty Images Mexico City earthquake in pictures Rescuers, firefighters, policemen, soldiers and volunteers remove rubble and debris from a flattened building in search of survivors after a powerful quake in Mexico City AFP/Getty Images Mexico City earthquake in pictures Rescuers and residents look for victims amid the ruins of a building knocked down by a magnitude 7.1 earthquake that jolted central Mexico damaging buildings, knocking out power and causing alarm throughout the capital on September 19, 2017 in Mexico City Getty Images Mexico City earthquake in pictures People try to rescue survivors from a collapsed buildings after a magnitude 7.1 earthquake on the Richter scale in Mexico City, Mexico, 19 September 2017. At least 79 people lost their lives in the states of Morelos, Puebla and Mexico by the earthquake of magnitude 7.1 on the Richter scale. EPA Mexico City earthquake in pictures People clear rubble after an earthquake hit Mexico City, Mexico REUTERS Mexico City earthquake in pictures People clear rubble after an earthquake hit Mexico City, Mexico REUTERS Mexico City earthquake in pictures Rescuers and residents assists an injured victim amid the ruins of a building knocked down by a magnitude 7.1 earthquake that jolted central Mexico damaging buildings, knocking out power and causing alarm throughout the capital on September 19, 2017 in Mexico City, Mexico. The earthquake comes 32 years after a magnitude-8.0 earthquake hit on September 19, 1985. Getty Images Mexico City earthquake in pictures People remove debris outside a collapsed building after an earthquake in Mexico City, Mexico REUTERS Mexico City earthquake in pictures People remove debris as they search for possible victims after a quake rattled Mexico City on September 19, 2017. A powerful earthquake shook Mexico City on Tuesday, causing panic among the megalopolis' 20 million inhabitants on the 32nd anniversary of a devastating 1985 quake. The US Geological Survey put the quake's magnitude at 7.1 while Mexico's Seismological Institute said it measured 6.8 on its scale. The institute said the quake's epicenter was seven kilometers west of Chiautla de Tapia, in the neighboring state of Puebla. AFP/Getty Images Mexico City earthquake in pictures A security guard walks over debris of a building which collapsed during a quake in Mexico City AFP/Getty Mexico City earthquake in pictures Reconstruction work in the towns affected by the telic movement has begun. Several temples suffered severe damage. Rex

Just hours after the initial reports of the earthquake, the disaster was trending on Twitter, and Facebook's check-in system for survivors during high concern situations had been activated. President Donald Trump, who had taken nearly a week to respond to a devastating earthquake in Mexico earlier this month, tweeted that the United States stood by the people of Mexico City.

"God bless the people of Mexico City," Mr Trump wrote in a tweet. "We are with you, and will be there for you."

At least one video, posted live on Twitter's Periscope, showed a group of men working together to try and move large metal beams. Nearby, cars were smashed by debris that had been shaken loose by the earthquake.

In another video, a building swayed sickeningly during the rumbling. Another showed people packing into a hallway with lights swaying above them, before the building appeared to lose power and the lights went out. In yet another video, the whole facade of a building that appears to be about 10 stories falls to the ground.

In a school in Mexico City's Roma district, Gala Dluzhynska described running alongside at least 11 other women from the second floor of the building. She described a terrifying scene to the Associated Press outside of her former school, saying that she and others had scrambled down stairs to get out of the building amid choking dust. At one point she fell down, and was trampled by others before someone going by grabbed her and helped her up.

"There weren't any stairs anymore, only rocks," she said.

Once she and the others got outside of the building, they attempted to push against the fencing until a security guard finally came and let them out. Outside was all rubble, she said. They were also still looking for one friend.