At least 250 people perished when powerful earthquake of magnitude 7.1 struck central Mexico on Tuesday afternoon, flattening buildings in the heavily populated capital, burying those unlucky under the ruins and the rubble.
The epicentre of the quake was reported to be near Atencingo in Puebla state, about 120km from Mexico City, with a depth of 51km, the US Geological Survey said.
A Reuters report said thousands ran out into the streets in panic as the quake struck around lunchtime. However, many also got stuck as electricity went off.
And, minutes, after the dust settled, the landscape was flattened with collapsed buildings and rubble all around, with rescuers frantically scouring under the rubble of ruins for survivors.
Mexico City Mayor Miguel Angel Mancera said 44 buildings were severely damaged or destroyed. Several major gas leaks and fires occurred.
While the quake had its greatest impact was in densely populated Mexico City, tremor was more intense in Puebla, closer to the epicenter, which was 30 miles deep.
The tremor lasted for just 20 seconds, but the waves reverberated for much longer, up to a minute or two, in the mountain and valleys.
Dozens of people scrabbled with bare hands to remove rubble from atop a concertinaed building as they waited for specialised machinery to arrive.
Central areas like Roma, Condesa and Doctores appeared to have taken the brunt of the 7.1-magnitude quake.
Several buildings were completely flattened in Roma, popular for its bars and restaurants and one of the neighbourhoods hit hardest by the 1985 earthquake that shattered large swathes of this city and killed at least 10,000 on the samre day 32 years ago.
Amid the tears and terror, there were small victories.
Cheers and applause echoed around the crowded Calle Alvaro Obregon in Roma as rescuers managed to pull someone from under the rubble.
There remained a sense that such moments would be rare, however.
In other buildings in the same area, volunteers joined the authorities to remove debris. One of them held a sign with the word "silence" in order to be able to hear people who may still be alive.
Seismologists said Mexico's earthquake was caused by crumpling from the downward bending of the sinking Cocos Plate deep within earth.
Plate tectonics along the coast of Mexico was the engine behind the shaking. The Cocos Plate slides underneath the North American Plate, moving about three inches per year.
Tuesday's earthquake, however, was reported to have been caused by crumpling arising from the downward bending of the sinking Cocos Plate, rather than directly by slippage between plates.