A former head of U.S. Immigration and Customs Enforcement (ICE) is criticizing the Trump administration's handling of the separation of migrant families at the southern border.

John Sandweg, who served as acting ICE director during the Obama administration, acknowledged on Hill.TV's "Rising" that family separations happened under former President Obama, but only in certain isolated cases.

“What this administration did on the family separation, by actively separating them, that was never done before on this scale, where there is an intentional program to take away parents from their children regardless of whether or not the parent poses a threat to the child,” Sandweg told Hill.TV co-hosts Krystal Ball and Buck Sexton.

“The bigger problem is — setting aside what you think about the policy — is that it was done very poorly, it was mismanaged, nobody tracked where the parents or the children were going,” Sandweg continued.

“Family separation did not happen like this under the Obama administration,” he said. “There were certainly isolated cases, where if you’re in the interior and you find somebody has been convicted of a felony, they have U.S. citizen children.”

The Trump administration has worked in recent weeks to reunite the thousands of migrant children separated from their families under the administration's "zero tolerance" border policy, which called for prosecuting all illegal border crossers.

Administration officials have said that the government met its court-ordered deadline to reunite migrant children with their parents by July 26.

According to a court filing, the government has reunited 1,442 families with children ages 5 and older, but hundreds of kids still remain in federal custody.

Sen. Dick Durbin Richard (Dick) Joseph DurbinThe Hill's Morning Report - Sponsored by Facebook - Trump previews SCOTUS nominee as 'totally brilliant' Feinstein 'surprised and taken aback' by suggestion she's not up for Supreme Court fight Grand jury charges no officers in Breonna Taylor death MORE (D-Ill.) this week called on Homeland Security Secretary Kirstjen Nielsen Kirstjen Michele NielsenMore than million in DHS contracts awarded to firm of acting secretary's wife: report DHS IG won't investigate after watchdog said Wolf, Cuccinelli appointments violated law Appeals court sides with Trump over drawdown of immigrant protections MORE to resign over the fallout, saying “someone in this administration has to accept responsibility.”

— Tess Bonn