Transcript for More than 200 dead after magnitude 7.1 quake strikes Mexico

We turn next to the other devastating scene unfolding right now. The catastrophic earthquake in Mexico. Buildings coming down. People trapped. So many of them children. Tonight, we're on the scene of a school collapse. Some of the children have been pulled out. And rescue crews shouting "Silence" so often today, in the moments they thought they could hear the children. ABC's Matt Gutman is on the scene tonight. Reporter: Tonight, hundreds still prying away debris, hoping to uncover a sign of life. A little girl, believed to be entombed in the rubble that was once her school, possibly communicate communicating with loved ones by text messages. First responders listening for a sign of life at the school. You see the hands up in the air. They've just called for silence. That means they a trying to listen to see if they can hear the person they're looking for inside still. That scene repeating itself all afternoon. Activity here has been intensifying. Right now, they are lifting that dog, right onto the roof of what was that school. That is the third dog we've seen in just the past couple of minutes. The calls for dogs and for doctors raising the hopes of a nation fixated on this school and desperate for good news. But so far, that missing girl has not been found. You can see the destruction from overhead. Silence written in huge letters. Through a window, children's backpacks still hanging on their hooks. 13-year-old Rodrigo narrowly escaping. He says, "We had to be evacuated by crawling over a wall." The school, one of dozens of buildings that collapsed in central Mexico when the massive 7.1 quake struck. Sending millions into the streets. Some capturing and sharing video of buildings crashing around them. Facades crumbling. Across Mexico City, the desperate search for survivors starting immediately, continuing through the night. And at the school, neighbors like Jesus among the first to rush into the rubble, hearing screaming from the inside. Then, making a grim discovery. We pulled out a kid and I saw, and they pulled his own sweater on his face and they pulled him out on the stretcher. Reporter: Was he alive? No. I don't think he was. Reporter: So far, at least 25 dead in the school alone. 11 rescued. These handwritten panels with the names of the wounded and their hospitals. Other notes listing the missing. David, an entire nation is fixated on the drama playing out just beneath me. We've been hear for eight hours, watching rescuers get closer and closer to that little girl. Right now, they seem tantalizingly close, but one thing they all say, they are not leaving here until they pull the last person out of that school. David? Matt Gutman right there in Mexico City.

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