(CNN) — Health and Human Services Secretary Alex Azar now estimates that under 3,000 kids who may have been separated from their parents are in government custody — a figure far higher than his department released just nine days ago.

HHS had previously reported that it had 2,047 children from separated families in its care.

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During a call with reporters, Azar said “a review and comprehensive audit of multiple data sets” undertaken by HHS and the Department of Homeland Security “has identified under 3,000 children in total, including approximately 100 children under the age of 5,” who he said are in the care of Office of Refugee Resettlement-funded grantees. The HHS secretary said that number refers to children “who may have been separated from their purported parents who were taken into DHS custody for having crossed illegally or for other reasons like concerns for the safety of the child.”

President Donald Trump reversed course last month and signed an executive order intended to keep families together, but the administration is still facing scrutiny and questions over the families separated as a result of its widely-criticized “zero-tolerance” immigration policy.

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The administration is now grappling with a series of court-imposed deadlines after a judge ordered the US government to halt most family separations at the border and the reunification of separated families.

DNA testing is being used as part of the effort to reunite children who were separated from their parents, a federal official with knowledge of the reunifications previously told CNN.

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