MSNBC host Rachel Maddow broke down in tears on Tuesday night reporting on family separations at the US-Mexico border.

A breaking story about "tender age" children being held in facilities in south Texas was the trigger.

The report said babies were being held in facilities away from their families in a potentially traumatic setting.

President Donald Trump's administration officials have described the children as being "well taken care of" in custody.

MSNBC host Rachel Maddow went off the rails on Tuesday night when it came time for her to read a new report of "tender age" children being detained away form their families at the US border.

Maddow broke down in tears and had to pass the show off to Lawrence O'Donnell, who hosts "The Last Word," the show that follows Maddow's on MSNBC.

"The AP has just broken some new news," said Maddow. "Trump administration officials have been sending babies and other young children," she read before pausing to collect herself.

"I think I’m going to have to hand this off. Sorry, that does it for us tonight. We’ll see you tomorrow,”she said while visibly trying to contain tears.

Later, on Twitter, Maddow apologized for breaking down, saying it was not "the way I intended that to go, not by a mile," and that she was trying to read the following passage from the Associated Press:

Trump administration officials have been sending babies and other young children forcibly separated from their parents at the U.S.-Mexico border to at least three "tender age" shelters in South Texas, The Associated Press has learned. Lawyers and medical providers who have visited the Rio Grande Valley shelters described play rooms of crying preschool-age children in crisis. ... Decades after the nation’s child welfare system ended the use of orphanages over concerns about the lasting trauma to children, the administration is standing up new institutions to hold Central American toddlers that the government separated from their parents. “The thought that they are going to be putting such little kids in an institutional setting? I mean it is hard for me to even wrap my mind around it,” said Kay Bellor, vice president for programs at Lutheran Immigration and Refugee Service, which provides foster care and other child welfare services to migrant children. “Toddlers are being detained.”

Maddow's show on the liberal-leaning MSNBC ranks as the most-viewed show of its type in its time slot.

President Donald Trump's administration officials have described the children as being "well taken care of" in custody.

The same Associated Press report quoted an official as saying the children are with "very well-trained clinicians, and those facilities meet state licensing standards for child welfare agencies, and they're staffed by people who know how to deal with the needs — particularly of the younger children."

But experts say that the mere act of separating children from their primary caregiver creates a traumatic experience for the child.

Trump maintains that this issue must be solved by Congress changing the laws around immigration. On Tuesday he met with Republican lawmakers and seemed to back a moderate compromise bill that could alleviate the situation, though it was drafted with no input from Democrats.

Watch the end of Maddow's show below: