Transcript for Death toll climbs over 200 after flash flood in Colombia

Next to, the epic disaster in South America. The death toll after a flash flood. A wall of water leveling a city as people slept in their beds, destroying homes and taking almost 200 lives. The grim list of the derngsd you see it there, and so many of them, children. Tonight, the rush to get water to survivors. Alex M Alex Marquard in Colombia. Reporter: Devastation and despair tonight deep in the Amazon basin. Rescue crews frantically digging through the muddy rubble trying to locate anyone who may still be alive, listening for sings of life. One feels completely unable to express the magnitude of the loss here, this man said, family members weeping over lists posted of mocoa's dead and missing children. We've lost a baby who's gone missing, this woman says. A little baby. We can't find him any where. The scale of the destruction from the avalanche of mud and water, staggering. Cars flung like toys, entire neighborhoods buried. The death toll tonight, at least 200, but with hundreds more still missing and injured, Colombian and aid officials expect it to grow. With water and power knocked out, obliterated roads and bridges hindering aid efforts, people trapped in flooded homes making desperate pleas to be rescued. It is very difficult because many people do not have the skills to let us know they're there. Reporter: Deforestation and climate change are being blamed for the scale of the destruction. A state of emergency has been declared in the area, where more heavy rain could complicate the already dire search and rescue efforts. Tom. At least 200 dead and the death toll expected to rise. Back to the states and a

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