As many as 3,000 migrant children remain in government custody after being separated from their parents at the border, more than a week after a court ordered the Trump administration to reunite families, Health and Human Services Secretary Alex Azar said Thursday.

The Trump administration is currently in the process of reuniting families, in part by using DNA tests to confirm whether they are related. But the government has yet to return children to their parents in immigration custody, Azar said. He said the administration will meet the extreme and arbitrary deadline imposed by the court to reunite families.

That means the families split up under President Donald Trump are only being reunited if the parent agrees to deportation or if the child was released to another relative in the U.S.

The Trump administration began a zero tolerance policy earlier this year to prosecute as many illegal border crossings as possible. That has included detaining parents separately from their children while they undergo brief criminal proceedings.

But the administration apparently did not keep clear records of which children it separated from their parents. Azar said officials are currently working through some 11,800 kids in government custody to determine which came with family and which were unaccompanied. Up to 3,000 children may have been separated from their parents, about 100 of whom are under the age of 5, he said.

That number is higher than the one the government previously cited for how many kids have been split from their families.

Some of those children were separated before Trumps zero tolerance policy began, or may have been split up from their parents when they were apprehended, Aza said. Government officials know where every child is and that they are being taken care of, Azar said.

Azar said the administration will use every minute of every day to confirm the parentage of children and to make sure they have a suitable caretaker. He said the court order limits the governments ability to do its typical screening process. He implied that quickly reuniting children with their parents could put them in danger, mentioning two instances of parents who were found to have criminal records including child cruelty, rape and kidnapping.

Azar blamed parents for the separations in the first place, repeatedly saying they should have gone to ports of entry or stayed home.