Transcript for Dozens killed in Mexican earthquake

right now, and they're awful. A massive earthquake, a powerful 7.1, dozens already reported dead tonight. You can see the buildings in Mexico City shaking wildly. Many of them collapsing. Workers then rushing into the streets. The people who did get out, dazed an trying to find their way through that smoke and that haze in the streets. Right now, rescuers are trying to get to people trapped. And there are real fears this evening that this death toll will quickly rise. ABC's senior national correspondent Matt Gutman leading us off tonight. Reporter: The scramble to unearth victims entombed by that quake. So powerful, it pulverized buildings. One woman covered in dust, carried through the crowd on a stretcher. Rescue workers racing into this badly damaged building, rushing this woman to safety. And from the air, it's easy to spot the devastation. Officials saying more than two dozen buildings collapsed, including schools. The massive 7. Quake striking just after 1:00 P.M. Less than 100 miles from the capital, Mexico City. Population, nearly 9 million. In this news room, overheadlights swinging like pendulums. Parts of the ceiling crashing down. Workers fleeing. One man steadying himself against the wall. Lights also swinging at this restaurant in Mexico City's airport. Tourists ducking for cover under a table. Thousands rushing to the safety of the street. "It was horrible, K" this man says. Outside, structures collapsing. Dust clogging the air. So thick, you can barely see anything. Oh, I pray that nobody's in here. Reporter: Residents seen trying to secure a billboard that landed on top of one of those collapsed buildings. We just lost a building. Mexico City. Reporter: Windows from this skyscraper crashing to the sidewalk. Streets littered with crumbling facades. This car destroyed. 250 miles away, in Mexico City. Reporter: It was 32 years ago today in which an 8.0 magnitude quake flattened parts of Mexico, killing thousands in 1985. Tonight, as the country begins to assess the earthquake's toll, more than 3.8 million residents are without electricity. The airport's operation suspended. The road in, now scarred with that giant crack. Just a horrific scene tonight. Matt Gutman with us. And Matt, the search and rescue efforts under way right now. Authorities say this death toll will go much higher into the night? Reporter: That's right, David. Largely, because there are still reports of people being trapped in the rubble. One of the main problems is that Mexico City was built on a lake bed, and it understood lates when an earthquake hits. Certainly a long night ahead for first responders. David? Matt ghaunt leading us off tonight. Matt, thank you.

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