NORTH TEXAS (CBSDFW.COM/CNN) — The Biden administration is facing challenges as the number of unaccompanied migrant children in US Border Patrol facilities reaches new highs.

More than 3,200 unaccompanied migrant children were in Customs and Border Protection custody, to internal agency documents dated Monday. Of those, around 2,600 were awaiting placement in shelters suitable for minors, but there were just over 500 beds available to accommodate them.

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The latest data comes on the heels of a trip to the US-Mexico border by senior administration officials to assess the situation on the ground amid an increasing number of arrests and indicates a rapidly increasing trend of unaccompanied children coming into the US. Less than a week ago, there were around 1,700 children in Border Patrol custody.

As of Monday afternoon, President Joe Biden had not yet been briefed by his top aides on the weekend trip, which included a visit to a facility for unaccompanied migrant children in Carrizo Springs, Texas — the first facility for migrant children to open since Biden took office.

The officials were in fact-finding mode, a person familiar said, and many were taking notes during their conversations. Biden is expected to be briefed in the coming days as aides spent some of the trip comparing notes and planning how to present the information to the President.

Among those who went was Susan Rice, former President Barack Obama’s national security adviser who now heads Biden’s Domestic Policy Council. A source familiar with the visit said Rice was engaged during the visit and, at times, pressed Department of Health and Human Services officials, who run the shelters for unaccompanied migrants, on how they were preparing to respond to the surge and process migrant children more efficiently.

In a statement Monday the Office of Refugee Resettlement said it “is aggressively working with our interagency partners to ensure that unaccompanied migrant children are safe and unified with family members or other suitable sponsors as quickly and safely as possible.”

“The number of unaccompanied children (UC) in our care is constantly changing,” the department said.

The growing number of unaccompanied children has raised alarm bells among officials scrambling to find shelter space to care for kids amid an ongoing pandemic that resulted in some locations keeping some beds unoccupied to comply with health guidelines.

Monday’s data reveals the continued bottleneck in the system, with more children coming into custody than the US government is prepared to care for. It also emphasizes the hurdles facing the Biden administration as it tries to strike a more humanitarian approach on immigration while juggling the realities on the border.

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The numbers are overwhelming. To compare, at the peak of the 2019 border crisis — when there were overcrowded facilities and children sleeping on the ground — there were around 2,600 unaccompanied children in Border Patrol custody, a former CBP official said.

A myriad of reasons can account for the sudden rise in children at the US-Mexico border, including the pandemic’s dramatic toll on Latin America, where economies once projected to grow have been decimated, the results of two devastating hurricanes that hit the region, and a perception of relaxed enforcement by the Biden administration.

Chief of staff to the first lady Julissa Reynoso briefly discussed her trip to the US-Mexico border as part of a delegation of the senior administration officials that also included Rice and Homeland Security Secretary Alejandro Mayorkas.

“We did speak to many of the folks involved, including children. We’re trying to manage this in an orderly fashion but very mindful of the human cost here, and in light of the fact that we are talking about kids. So that is something that we are managing,” Reynoso told reporters Monday.

The group flew from Washington on a military plane and made their first stop at the CBP tent facility in Donna, Texas, in the Rio Grande Valley, which has been processing undocumented migrants. From there, the group flew north along the border to Laredo, where they landed and drove to the facility housing children in Carrizo Springs. The trip lasted most of Saturday.

At the two sites, the officials spoke with some of the people who are in charge of running them, some of the rank-and-file CBP and HHS officials working there and a few of the migrants who are being held in the facilities, including some of the children. Several of the officials on the trip speak Spanish and could communicate directly with the migrants who were being held.

On Friday, the Biden administration notified facilities caring for migrant children that they can open back up to pre-COVID-19 levels, acknowledging “extraordinary circumstances,” according to a memo.

After being taken into Border Patrol custody, unaccompanied children have to be turned over within 72 hours to the Department of Health and Human Services, which is tasked with the care of migrant children, barring exceptional circumstances.

Once in care, case managers will work to place children with a sponsor, like a parent or relative, in the US, but as a result of the coronavirus pandemic, and precautions to avoid spread of Covid-19, the department has only been able to use a little more than half of the beds it has for children.

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