WASHINGTON – A new 32-page report from the House Oversight Committee's staff says the Trump administration's "zero tolerance" immigration policy resulting in the separation of migrant children from their families between April and June 2018 was "more harmful, traumatic and chaotic" than previously known.

Under a "zero tolerance" immigration policy, the Trump administration prosecuted all cases of unauthorized border crossings, meaning that migrant families who crossed the border were separated.

Parents were referred by Customs and Border Protection (CBP) for prosecution while children were designated as Unaccompanied Alien Children (UAC) and taken into custody by the Office of Refugee Resettlement, part of the Department of Health and Human Services. President Donald Trump ended the policy after it sparked a national political backlash.

The report, based on subpoenas issued in February to the Departments of Justice, Homeland Security, and Health and Human Services, found:

"At least 18 infants and toddlers under two years old were taken away from their parents at the border and kept apart for 20 days to half a year"

"At least 241 separated children were kept in Border Patrol facilities longer than the 72-hour" maximum allowed under federal law

"At least 679 were held for 46 to 75 days, more than 50 were held for six months to a year and more than 25 were held for more than a year"

"Even after being reunited with their parents, hundreds of separated children continued to be detained for months in family detention facilities – far longer than the 20-day limit under the Flores case." The Flores agreement is a court-ordered agreement between the federal government and immigrant advocates governing the treatment of migrant children.

"At least 10 separated children were sent to the 'tent city' in Tornillo, Texas, the notorious emergency influx facility near El Paso"

"At least 30 children separated from their parents under the zero-tolerance policy remain separated"

The committee's investigators noted they were still waiting on additional information from federal agencies under the subpoenas, which could result in more updates to the report.

"The administration executed a deliberate policy to take thousands of babies, infants, toddlers, and children away from their parents and transfer them to government custody, in some cases in deplorable conditions," the report concluded.

The report's release comes as the House Oversight Committee holds a hearing on child separations on Friday morning.

House Oversight Committee Chairman Elijah Cummings started the hearing on Friday discussing migrant detention and the separation of families by highlighting the findings, which he described as a “nightmare.”

“The evidence shows that the administration’s policies are causing the problems at the border, not helping to resolve them,” said Cummings, D-Md., specifically highlighting the Trump administration’s zero-tolerance policy and saying it has contributed to “massive overcrowding” in the facilities.

The Trump administration has faced increased scrutiny of its migrant detention policies following the release of a Department of Homeland Security inspector general report showing children in Border Patrol custody in the Rio Grande Valley were held in unsafe and unsanitary conditions. At least six migrant children have died in federal custody since December.

More:‘They tore out a piece of my heart’: Migrant mother describes toddler’s illness, death

More:Mike Pence heads to border to defend migrant facilities as Democrats decry 'unconscionable' conditions

More:'A lot more needs to be done for them': Ex-CBP chief explains why he left the Trump administration, report says

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