Leaked document: More than 800 migrant kids held in cage-like facilities for over 10 days. The max time allowed is 72 hours.

A recently leaked Department of Homeland Security document obtained by Axios revealed that thousands of migrant children are being held in Border Patrol surge facilities longer than is legally allowed — with 823 of them being kept in the cramped, cage-like units for more than 10 days.

Under current law, 72 hours is the maximum amount of time that a child is legally allowed to be in Border Patrol custody, after which they are to be transferred into longer-term facilities operated by the Department of Health and Human Services.

However, in the first weeks and months since assuming power, President Joe Biden and his administration have been unable to manage the crisis, as unprecedented numbers of migrants descend on the U.S.-Mexico border in hopes of lenient treatment under the new president.

The news outlet reported Monday that "as of Saturday, 3,314 unaccompanied children had been in custody longer [than is legally permitted], with 2,226 for more than five days and 823 for more than 10 days."

The Washington Post reported earlier this month that many migrant children are being held for longer than three days. But on Monday, Axios reported that the new numbers exhibit "more than a fourfold increase over the past week," a sign that the problem is only worsening.

"Last Monday, only 185 migrant children were being held in [Border patrol] custody for more than 10 days," the report stated.

Part of the reason the law dictates that children can only be housed in Border Patrol custody for 72 hours is simply that the temporary surge facilities operated by the agency are not suitable to house children for any longer.

Photos leaked by Texas Democratic Rep. Henry Cuellar's office on Monday from inside a surge facility in Donna, Texas, show hundreds of children packed into small makeshift rooms with nothing but thin mattresses and bedding materials.

Conditions inside facilities like the one in Donna have been previously described by media organizations as "grim," cage-like, and "akin to jails."

Cuellar described the setting as "terrible conditions for the children," adding that Border Patrol agents were "doing the best they can under the circumstances" but are "not equipped to care for kids" and "need help from the administration."

To free up space inside both shorter- and longer-term facilities, the Biden administration has reportedly decided to spend $86 million in taxpayer money to pay for hotel rooms to accommodate migrant children and their family members.