(CNN) Detainees at a central processing center in McAllen, Texas, were "frightened" and told Massachusetts Democratic Sen. Elizabeth Warren that America is their "last hope," she told CNN after leaving the center Sunday.

"We talked to mothers who just said, from Honduras in particular, who said, 'there's nothing there for us. ... America is our last hope,'" Warren said.

Warren also told CNN that she repeatedly asked detainees if they were happy to be there, and that they replied, "'yes, we are in America.'"

At the center, there "are big chain-linked cages on concrete floors and metal blankets [being] handed out to people," Warren said, adding that the detainees "are frightened."

Warren also addressed President Donald Trump's tweet earlier Sunday about detainees, stating that the United States "must immediately, with no Judges or Court Cases, bring them back from where they came."

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