Transcript for Human rights activists announce 24-day hunger strike in Texas

Next to that rising border chaos, the dramatic protests today, demonstrators shouting in a showdown. In McAllen, Texas, the whereabouts of 2300 children stl in question tonight. ABC's Marcus Moore is there for us tonight. Reporter: Tonight, emotions boiling over on the border. In McAllen, Texas, the epicenter of the crisis, demonstrators blocking a bus full of immigrant children, creating a tense stanoff between protesters and police. Set those children free. Set those children free. Reporter: Human rights activists announcing a 24-day fast in support of separated families. What is the significance of a fast in thisituation? People are sacrificing. They're feeling ttle bit of pain, maybe hunger pains. But not the kind of pains that these families are suffering O that these children are feeling. Reporter: The customs and borer protection agency says 500 children in itcustody have been reunited but there are still more tn 1800 at other agencies, separated fr their parents. Among them, 8-year-old Danny, 'S in new york.his mother, being detained I El Paso, facing charges after crossing the border illegally. His aunt, nilaerrano, trying to reute them. The El Paso processing center S not responded. We've already bought the bus cket, ready to go. She's not even aware that she's not coming home us. Reporter: The fogf certainty fueling frustratio and calls for expedited reunions like this one in Baltimore on Friday. Others who have been deported like these families in hondura king solace in seeing their loved ones. While in Texas, buses drop off young mothers and theichildren at this station, daily. They wear ankle monitors, as they wait for word on their asylum cases, and a nationwide debate rages on. And Marcus joins us from from near the border tonight. Marcus, a delegation of lawmakers toured a processing center tonight. They want more transparency to show what's going on inside. Reporte whit,'s that's right. They're still urging government officials to allow heath professionals to inside these facilities, to monitor these children's mental health. Health and human services has foed a task force to work on returning thousands of children to their families, whit. All rightmarcus Moore, thank you. And more on the national debate over immigration tomorrow on "This wk." When George stephapoulos goes one-on-one with senator Jeff flake and representative Luis Gutierrez.

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