Transcript for 4-legged hero among the first responders in Mexico City

. And finally tonight, amid so much devastation this week the story of frita, the dog leading teams through the rubble. Chef has saved lives before and many of them. This week in Mexico those moments of heroism giving so many renewed hope that more lives would be saved. Firefighters rescuing this woman pulling her out through a hole in the ceiling. Her hand to her face in disbelief. Children trapped inside this school. Rescuers and neighbors pushing through the rubble. Reaching behind this wall to lift them out. And among the first responders are at that school, frita. The 7-year-old Labrador is part of the Mexican Navy's canine unit searching for trapped survivors. She has saved a dozen lives in her career. In those goggles protecting her eyes from the dirt and debris and the booties to protect her paws. They have been crawling into those dangerously tight spaces for days now. The corners rescuers cannot get to. Tonight as hope fades so many trying to focus on the lives saved. And the first responders and their partners, those dogs including frita answering the call again. Cannot forget frita and those dogs with all of those rescue teams. Thank you for watching this week. I'm David Muir. I hope to to see you on Monday until then have a good evening.

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