(CNN) The number of unaccompanied migrant children in border facilities reached its highest point on Sunday since the federal government began releasing data last week.
There were 5,767 children in Customs and Border Protection custody on Sunday, up from 5,495 children on Thursday. The numbers have gone up each day the data has been released, and Sunday marks the most recent data available.
The overall number of unaccompanied migrant children in US government custody, however, ticked down slightly from more than 18,000 children last Thursday to around 17,650 on Sunday, the data shows.
The latest custody data illustrates how the Biden administration continues to struggle with large numbers of unaccompanied children in its care, particularly in its inability to move kids out of border facilities and into more appropriate Health and Human Services custody.
Internal government estimates previously obtained by CNN indicate that the Biden administration could need at least 34,100 additional beds to keep up with the projected number of unaccompanied kids arriving at the US-Mexico border through September.
The internal estimates take into account current trends as well as previous influxes of migrant children, and show an anticipated month-by-month increase that could result in at least 158,000 unaccompanied children arriving from April through September.
The number of children apprehended by CBP and placed in border facilities on Sunday again outpaced the number of children transferred to HHS, the agency charged with caring for migrant minors once they enter the US.
While the President committed to making immigration reform legislation a priority of his administration, Congress has long been unable to garner enough bipartisan support to pass any legislation to change the country's immigration system.
During his first news conference as president last week, Biden promised conditions for unaccompanied minors arriving in the US will improve and blamed the prior administration and the cooler weather for the spike of migrants at the border.
"The reason they're coming is that it's the time they can travel with the least likelihood of dying on the way because of the heat in the desert, number one. Number two, they're coming because of the circumstances in country," Biden said.
Though border arrivals typically rise in the spring, the Covid-19 pandemic has exacerbated the situation and further limited the capacity along the border to process migrants.
To compare, in May 2019, at the height of that crisis, 11,475 unaccompanied kids were arrested by US Border Patrol. In June 2014, during the peak surge of children at the border, 10,620 unaccompanied children were arrested by US Border Patrol.
This story has been updated with additional information Monday.