In June 2018, just a few days after President Donald Trump announced the end of the “zero-tolerance” immigration policy that led to the breaking up of thousands of families at the border, the Department of Homeland Security released a fact sheet claiming the administration knew, from a “central database,” the location of all children in its custody and had “a process established to ensure that family members know the location of their children.”

But in reality, according to emails the House Judiciary Committee provided to NBC News, the administration had no database with information for both parents and children and no clear way to match them. Instead, DHS and the Department of Health and Human Services, which cares for migrant children in government custody, were hurrying to populate a single spreadsheet with the necessary data.

“[I]n short, no, we do not have any linkages from parents to [children], save for a handful,” an HHS official told an ICE official in an email on June 23. “We have a list of parent alien numbers but no way to link them to children.”

The administration admitted at the time that the process of reunification would be a long one. It took months to reunite the nearly 3,000 families as officials had to review documents for the children and parents manually. Almost a year later, several dozen children separated from their families under the zero-tolerance policy remain in HHS custody.

At the time, according to the emails, an HHS official emailed an ICE official asking for identification numbers for the parents. “[T]he type and volume of what you are requesting is not something that we are going to be able to complete in a rapid fashion, and in fact, we may not have some of it,” the ICE official replied. The HHS official wrote back that he only had information for “about 60” parents.

While former DHS Secretary Kirstjen Nielsen claimed multiple times that the Trump administration was keeping track of the separations, one official said the information DHS provided to HHS was too incomplete to be able to easily reunite families. In September, the DHS Office of Inspector General also concluded that there appeared not to have been a complete central database for parents and their children.

HHS and DHS denied in statements to NBC News that it had neglected to create a system to connect children to their parents.