HIDALGO, Texas (NewsNation Now) — U.S. border officials estimate that up to 184,000 unaccompanied migrant children could arrive at the U.S.-Mexico border this year, according to internal government data reviewed by Reuters.

The estimate underscores a growing challenge for President Joe Biden as his administration struggles to house a rising number of mostly Central American children arriving at the border without a parent or legal guardian.

An internal document by U.S. Customs and Border Protection (CBP) projects that 159,000 – 184,000 unaccompanied children could arrive at the southwest border in fiscal year 2021, which began on Oct. 1, 2020.

If the estimate is accurate, it would be higher than any other year on record since 2010, when CBP began to fully track apprehensions of unaccompanied children, the classification given to youth who may have arrived alone, with smugglers or relatives other than their parents.

The next-highest annual total occurred during a spike in 2019 under former President Donald Trump. During that fiscal year, roughly 76,000 unaccompanied children were taken into custody at the border.

CBP estimates that about 15,000 unaccompanied children arrived at the U.S.-Mexico border in March. The figure is based on data through March 19 and official statistics are not expected to be available until early April.

If the estimate is accurate, the 15,000 arrivals will be the highest monthly total since 2010. The previous high was in May 2019, when about 11,500 unaccompanied children were taken into custody. CBP estimates that four times as many unaccompanied children could be held in government-run shelters by September.

Recently surfaced surveillance video shows a smuggler dropping two small children over the U.S. Mexico border wall and abandoning them. 

Border Patrol says the smuggler then returned to the Mexico side of the border, joined another smuggler and ran away.

Agents took the young girls — who were not harmed — to a local hospital to be checked out. They were then taken to a temporary holding facility

The shelter system, overseen by the U.S. Department of Health and Human Services (HHS), had a little over 12,000 children in custody as of March 29. The figure could grow to 53,000 by September, requiring HHS to add tens of thousands of additional shelter beds, according to the internal estimate.

The HHS refugee office has struggled to keep up with hundreds of arriving children each day, leaving kids stuck in crowded border stations and processing centers for days.

However, the new CBP estimates come with some caveats:

• The estimates exclude Mexican children, most of whom can be quickly returned to Mexico under a bilateral agreement.
• The projections also assume the Biden administration will not change its policies toward unaccompanied minors, as new policies could lead to different estimates.

CBP and the HHS refugee office did not immediately respond to requests from Reuters for comment.

The Biden administration let journalists tour the migrant holding facility in Donna, Texas for the first time Tuesday, with permission for photos and video to be shot. That access came after months of pressure by news organizations to be allowed access. CBP said the pandemic had forced limits on how many journalists could participate.

The administration has not allowed journalists to view a holding area under an international bridge in Mission, Texas, and has avoided ride-alongs with Border Patrol agents. HHS has not allowed reporters into any of the emergency sites across the Southwest to take children from CBP.

By comparison, in 2018 the Trump administration allowed reporters to tour its main holding facility in McAllen, Texas, but did not allow journalists to take photos or video. It provided its own images instead. In the Obama administration, an AP photographer toured an Arizona facility for children in 2014 and distributed those images under a pool arrangement.