Rescue workers dug through broken pieces of concrete overnight in Mexico City, trying to uncover children trapped under what used to be an elementary school.
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A 7.1-magnitude earthquake struck Mexico Tuesday afternoon, killing at least 225.
READ MORE: At least 217 people killed after major 7.1 magnitude earthquake strikes near Mexico City
Large crowds gathered outside the Enrique Rebsamen school, as military and rescue personnel pulled out the bodies of at least 22 children. The schoolchildren are between the ages of three and 14.
About 30 children and 12 adults are still missing after the collapse of the school, which is just one of the dozens of buildings destroyed by the natural disaster.
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Three survivors were found around midnight as volunteer rescue teams crawled deep under the rubble. There were some reports of teachers and students sending text messages, asking for someone to rescue them.
Crowds of parents waited outside for hours, many crying and praying that their children would be found alive.
“They keep pulling kids out, but we know nothing of my daughter,” one mother told Reuters.
Dr. Pedro Serrano, a volunteer helping with the efforts, told The Associated Press that he crawled through a small opening in the rubble into a classroom, only to find all occupants dead.
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“We saw some chairs and wooden tables. The next thing we saw was a leg, and then we started to move rubble and we found a girl and two adults — a woman and a man,” he said.
Tired and wary, Serrano and others continued the hours-long search, asking onlookers to be silent so they could hear calls for help.
“We can hear small noises,” he said. “We don’t know if they’re coming from above or below — from the walls above (crumbling), or from someone below calling for help.”
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Rescue efforts are also underway in other parts of the Mexico City area, which is home to about 20 million people. As many as 4.6 million facilities, including homes and businesses, are without electricity.
The earthquake occurred on the anniversary of the deadliest earthquake in the country’s history. The 1985 earthquake killed 5,000 people.
— With files from Reuters, The Associated Press