Luis Alberto Castillo, a father of one from Venezuela, entered the United States on Jan. 19, one day before Donald Trump became president for a second term — swept into office on a promise to treat undocumented migrants with a heavy hand.
By Feb. 4, Mr. Castillo was on a plane to a U.S. Navy base at Guantánamo Bay in Cuba, best known for a detention center that has long held terrorism suspects accused of launching the deadliest attack on American soil.
That day, the Department of Homeland Security declared that those who had been transferred to the island represented “the worst of the worst” and were all members of a Venezuelan criminal group, the Tren de Aragua.
But in interview from her home in Colombia, Mr. Castillo’s sister Yajaira Castillo said her brother was not a gang member to be feared, but rather an everyday Venezuelan who had fled his country because of its economic crisis.
She broke down repeatedly during the conversation, crying as she described her pain and confusion around her brother’s situation.
“My brother is not a criminal,” she said. “This is all discrimination and xenophobia, just because he’s Venezuelan.”