About 15 migrant children recently separated from their parents near the southwestern U.S. border are staying at a shelter in Northern Virginia, according to the shelter’s leadership.

Sen. Tim Kaine (D-Va.) toured the Youth for Tomorrow facility Friday in the Prince William County community of Bristow, aides said, speaking with some of the migrant children and learning from the staff that many of the youngsters arrived there “traumatized.”

The children — girls from 10 to 17 years old — were taken to the shelter, according to Gary Jones, chief executive of Youth for Tomorrow, after the Trump administration began a recent, highly publicized immigration enforcement crackdown.

Jones said two of the girls are expected to be reunited with their parents soon. He said he did not have additional details.

The administration’s “zero tolerance” approach emphasized prosecution of adults who cross the border illegally, which led to children being taken from their parents and housed in shelters, while the parents were placed in criminal detention.

President Trump signed an order this week meant to end family separations at the border, although the details of implementing it remain unclear.

“The Trump administration needs to assure us that every single one of the children they separated from their parents is quickly and safely returned to their families,” Kaine said in a statement. “The first step toward that goal is identifying where every child is being held, releasing a list of those facilities, and letting members of Congress visit all of those locations.”

Kaine said he was thankful that Youth for Tomorrow allowed him to visit and appreciated the organization’s efforts to reunify families. He contended that federal authorities are not being transparent about the locations where children are being kept.

Jones said Youth for Tomorrow is sheltering dozens of migrant children from Honduras, Guatemala and El Salvador. Most arrived at the U.S.-Mexico border alone, he said, but about 15 had traveled with parents.

“Here’s the thing that agitates some of us: Every single kid here has been separated from their families,” Jones said. “There are families that send their kids here by themselves. It’s not right that we’re separating children from their families when they come across the border, but every child they have here has been separated from their families if they’re an immigrant child. Every single one.”

At least 2,500 migrant children were separated from parents under Trump administration actions starting in early May. The federal Office of Refugee Resettlement, part of the Department of Health and Human Services, has placed many of them in shelters and foster homes around the country.Lawmakers and state officials have pressed for a detailed accounting of those arrangements, so far with limited success.

A media unit within the HHS Administration for Children and Families did not respond to an email from The Washington Post this week seeking information about the number of separated children sent to Maryland and Virginia.

Efforts to track the separated children face bureaucratic hurdles. They are being handled under the same process the government uses to shelter undocumented migrant children who come to the United States unaccompanied by parents.

The Capital Area Immigrants’ Rights Coalition said four shelters in Virginia and two in Maryland are designated to receive unaccompanied migrant children. Some separated migrant children are also living in foster homes in Maryland.

A spokeswoman for Maryland Gov. Larry Hogan (R) said his administration has requested information from the federal government about the placement of separated children in the state.

Hogan, who withdrew a National Guard helicopter crew from the southern border this week to protest the family separations, “believes any children located in Maryland should be reunited with their families,” spokeswoman Amelia Chasse said in an email.

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