Updated at 7:45 p.m. ET

As the morning sun rose over the cities of Central Mexico on Wednesday, where city blocks had lain neatly arranged, there was now a mess of rubble and stunned residents, watching as thousands of earthquake volunteers and rescue workers dug through scattered stones searching for signs of life.

The 7.1 magnitude quake struck Tuesday in Puebla state, some 75 miles from Mexico City, but it devastated a vast expanse of the country. Mexican authorities put the death toll at 230.

That number is expected to change as more rubble is pulled away.

In Mexico City, where the agency says 93 people died, search efforts took on particular intensity at a collapsed school. Escuela Enrique Rebsamen — a school geared toward children ages 3 to 14, according to Reuters — caved in on dozens of students and their teachers Tuesday.

Rescue workers have found the bodies of at least 25 people, including 21 children, according to Mexican Education Minister Aurelio Nuño. He has said at least 30 more people are missing, though hope remains: In the late morning local time, Nuño said 11 people had been rescued.

The rescue efforts have also yielded terrible discoveries, too. One volunteer had managed to dig his way into a collapsed classroom, The Associated Press reports, "only to find all of its occupants dead."

"We saw some chairs and wooden tables," he told the news service. "The next thing we saw was a leg, and then we started to move rubble and we found a girl and two adults."

Yet families have not relented in their search.

"By the school," NPR's Carrie Kahn reports, "there's an intersection with a bunch of string that's been tied between trees and people have put the names of the children in the school up there. It's just filled with sheets of white paper with names scribbled on them."

Across the city, Mayor Miguel Ángel Mancera said at least 52 survivors have been pulled from the rubble.

Elsewhere, in the state of Morelos, at least 69 people died, while the earthquake's effects killed at least 43 people in Puebla state. And 18 others died in three other states in the region.

One of the areas hardest hit by the quake is Jojutla, the Morelos state municipality near the epicenter where at least 1,800 homes and businesses were severely damaged, according to The Guardian — some 300 of which were destroyed. The paper, citing local news outlets, reports that every single building in the town center showed signs of damage.

Mexican President Enrique Peña Nieto toured the town Wednesday, promising coordinated support to the devastated area.

In a stroke of terrible coincidence, Tuesday's earthquake struck 32 years to the day of one of the worst temblors in the country's history. That 1985 quake took thousands of lives and shattered cities, including Mexico City, wreaking such destruction that the country continues to mark its anniversary with simulated-quake drills.

In fact, as Emily Green reports for NPR, not two hours before Tuesday's temblor hit, sirens blared in cities across the country to commemorate the deadly event and prompt residents to practice evacuation drills.

Shortly after those residents returned to their buildings, they felt those same buildings rattle. One witness had been standing in a Mexico City plaza when the shaking came.

"The trees were moving. I thought maybe the trees would fall over us. It was just a nightmare," she told Emily. "That's the best way to describe it: a really bad nightmare."

Peña Nieto spoke over the phone with President Trump, who "offered assistance and search-and-rescue teams, which are being deployed now," according to the White House.

The Mexican president declared three days of national mourning to commemorate the earthquake's victims.

"The priority continues to be rescuing the people in collapsed structures and to tend to the injured. Every minute counts towards saving lives," Peña Nieto said in a series of tweets. "I am grateful and recognize the thousands of volunteers and public servants that are participating in the rescue work."

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