The Donald Trump administration announced Thursday it has reunited a little more than half of the children under 5 years of age with parents whom it separated at the U.S.-Mexico border.

Axar.az informs citing AA.

In all, the administration reunified 57 of the 103 undocumented children it separated, the Department of Homeland Security said in a statement.

The additional 46 were found to be ineligible by a court or the administration due to a broad range of factors.

The bulk of those who were found to be ineligible -- 24 -- were determined not currently eligible due to the status of their corresponding adults. Half of the adults have already been deported and the administration is working to contact them. Eleven others are either in custody for other unspecified offenses, while the last adult's whereabouts are unknown.

Still, 22 other children were deemed unsuitable for reunification due to safety concerns posed by the adults the children would be returned to, including 11 who have serious criminal histories, according to the administration.

Seven other adults were determined to not be a parent. One adult had a falsified birth certification. One allegedly abused a child. Another planned to house the child with an individual charged with sexually abusing a minor. The last adult listed by the administration is being treated for a communicable disease.

"There remains a tremendous amount of hard work and similar obstacles facing our teams in reuniting the remaining families," Attorney General Jeff Sessions, Department of Homeland Security Secretary Kirstjen Nielsen and Health and Human Services Secretary Alex Azar, said in a rare joint statement.

Their departments were responsible for the reunifications after the administration chose to separate the children from their families under President Donald Trump's hardline "zero tolerance" immigration crackdown.

"The Trump administration does not approach this mission lightly, and we intend to continue our good faith efforts to reunify families," the trio of department heads added.

The administration missed a Tuesday deadline to complete the reunifications for children under 5 whom it separated. Following Thursday's announcement, the administration faces another deadline July 26 to reunite the remainder of the more than 2,000 children who remain separated from their families.

Trump's hardline immigration policy refers all apprehended undocumented adults for criminal prosecution -- a break with past administrations who limited criminal referral for most adults who illegally cross into the U.S. with their juvenile family members.

A court ruled earlier this week that the administration cannot detain immigrant families long-term, upholding a 20-day time limit a child can be held in custody, and casting into doubt the future of Trump's immigration agenda.

U.S. District Court Judge Dolly Gee said in her ruling that the administration's reasoning is "tortured" and a "cynical attempt" to shift immigration enforcement duties to the judiciary.