Experts say that, usually, there is little to no chance of finding quake survivors after three days.
"Since September 7 it has not stopped shaking", he said. "We'll be sending more personnel over there, to check on everything now". So many people turned out to help find survivors or rescue bodies that authorities had to start turning volunteers away.
In Mexico City alone, at least 186 people are confirmed dead, and at least 44 are still missing or unaccounted for at the last official search and rescue site, an office building located at 286 Álvaro Obregón Avenue. People formed human chains to pass along supplies and remove chunks of lumber and concrete. RMS, a risk modelling company, estimated economic losses of up to US$8 billion.
"Time has gotten the best of us".
The Popocatepetl volcano south of Mexico City sent a column of ash into the sky, capping an intense period of seismic activity including two powerful tremors this month that have killed more than 400 people and caused damage of up to $8 billion.
Rescuers have temporarily evacuated from the wreckage of a seven-story office building in Mexico City that collapsed in Tuesday's magnitude 7.1 quake.
The government of Oaxaca state reported that some homes collapsed.
"There are limits to what can be done when there's buildings constructed decades and decades ago, (and) there's lots of informal settlements", said UNISDR's Glasser.
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Measures such as adding structural walls, taking out windows and putting in supports are pricey, but substantially improve building safety in earthquake-prone areas, said Mary Comerio, a professor of the graduate school at the University of California, Berkeley.
"You said you would be with me always", his daughter, Claudia Ponce, 30, told him.
Mexico City's mayor, the education minister, and the top official for the district all traded blame after reports that the Enrique Rebsamen primary school operated using false documents.
While rescuers work around the clock at disaster sites, dozens of police and military forces are left without any apparent task, sometimes just standing by, inactive.
"You are making the State of Israel very proud", he said.
Many Mexicans remember "miracle" rescues a week after a 1985 quake that killed more than 10,000 people in the capital, spurring hopes that some might yet be pulled out alive.
The tremors were mild in Mexico City.
Hope mixed with fear Friday on a 60-foot stretch of a bike lane in downtown Mexico City, where families huddled under tarps and donated blankets, awaiting word of their loved ones trapped in the four-story-high pile of rubble behind them.