Senate Democrats on Tuesday criticized the Trump administration’s efforts to reunify hundreds of undocumented migrant children who remain separated from their parents as a result of the president’s zero-tolerance border security policy — including many whose parents have already been deported.

Officials from the departments of Homeland Security and Health and Human Services told the Senate Judiciary Committee that their court-ordered work to reunify separated families is unfinished.

But Democrats who have expressed outrage over the policy weren’t satisfied, probing the officials to explain why steps were not taken to plan for the reunification process before the separations took place.

“There were some very basic ways that we could have kept track of the children and their parents in this age of, not only computers, but plastic bracelets,” said Senate Minority Whip Richard J. Durbin, D-Ill.

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