As the morning sun rose over the cities of Central Mexico on Wednesday, where once city blocks had lain neatly arranged, there was now a mess of rubble and despair-stricken 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. The head of Mexico’s civil defense agency said early Wednesday that 225 people had died in the temblor, in toppled buildings across five states and in the capital.

In Mexico City, where the agency says 94 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 22 of those children and two adults, according to Mexican President Enrique Peña Nieto. Reuters reports at least 40 more people are missing, though hope remains: At midnight, the wire service says three people were saved from the debris.

Yet 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.”

#Actualización: Suman 225 fallecidos: 94 #CDMX, 71 #Morelos, 43 #Puebla, 12 #Edoméx, 4 #Guerrero y 1 #Oaxaca.

— Luis Felipe Puente (@LUISFELIPE_P) September 20, 2017

Elsewhere, in the state of Morelos, at least 71 people died, while the earthquake’s effects killed at least 43 people in Puebla state. And 17 others died in three other states in the region.

In a stroke of terrible irony, Tuesday’s earthquake struck 32 years to the day to 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 drills.

In fact, as Emily Green reports for NPR, not two hours before Tuesday’s temblor hit, sirens rang out 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 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.”