Transcript for Thousands flee Venezuela daily as Maduro blocks US aid

Next to the humanitarian crisis in Venezuela. Thousands fleeing daily, those left scrambing for dwindling supplies in ABC's Victor Oquendo along the border with the human toll. Reporter: Tonight, reinforcements on the bridge. These Venezuelan soldiers bolstering the blockade ordered by Venezuela's president Nicholas maduro to keep potentially life-saving aid away from their own people. Truckloads of necessities in limbo inside this Colombian warehouse -- rice, toothpaste, and medical supplies nearly impossible for most people to find, much less buy, in Venezuela. Thousands in desperation crossing this border by foot daily. Elizabeth Salazar made that same journey with stage four breast cancer. For almost two years you had breast cancer and you couldn't get medicine. You had to come to Colombia. She's finally undergoing chemotherapy in Colombia and says she won't return home. Her husband, once a political prisoner in Venezuela, sewing his mouth shut while imprisoned, going on a hunger strike, tells us their children can't visit their mother. Reporter: As the political standoff between Nicolas maduro and interim president Juan guaido drags on, it's the ordinary people who suffer most. Tom, there is more humanitarian aid on the way, but the question is, will any of it get in? The U.S. Is leading the efforts at the request of opposition leader and interim president Juan gauido, who promises to get those supplies to his people. What we saw in the warehouse could help thousands but there are millions suffering, making it more of a symbol in the standoff between him and maduro, the two men who claim to be the leaders of Venezuela. Tom. Victor, thank you. And there's still much more ahead on "World news tonight"

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