• The Biden administration is under scrutiny as critics say the White House was not prepared for a surge in unaccompanied children arriving at the U.S.-Mexico border.
• Record numbers of children being held in jail-like Customs and Border Protection facilities, including thousands beyond the 72-hour legal limit.
• DHS chief Alejandro Mayorkas would not provide a timeline Sunday on when the administration will be able to adhere to the 72-hour limit.
• DHS is also facing criticism for denying media requests to see the facilities where unaccompanied children are being held.

Department of Homeland Security chief Alejandro Mayorkas said Sunday that the surge in unaccompanied minors at the U.S.-Mexico border poses an unprecedented challenge because of actions taken under former President Donald Trump, as critics accuse the current White House of being unprepared for a humanitarian crisis at the nation's doorstep.

"There was a system in place in both Republican and Democratic administrations that was torn down during the Trump administration, and that is why the challenge is more acute than it ever has been before," Mayorkas said on CNN's "State of the Union."

Mayorkas appeared on CNN, NBC and Fox on Sunday to defend the administration of President Joe Biden as it faces scrutiny over record numbers of children being held in jail-like Customs and Border Protection facilities, including thousands beyond the 72-hour legal limit.

The Biden administration reversed a Trump-era policy of expelling unaccompanied minors apprehended at the border, instead allowing them into the United States for processing. Republicans, Democrats and human rights activists have criticized the conditions under which children are being held.

Critics have said that the change in policy has encouraged unaccompanied children to make the perilous journey at a time when the U.S. does not have the infrastructure in place to properly care for them.

Mayorkas has previously said there is no crisis at the border, though he has acknowledged that the U.S. is on pace to encounter more individuals on the southwest border than anytime in the last two decades.

The Biden administration has deployed the Federal Emergency Management Agency to move children quickly into the care of the Department of Health and Human Services until they are placed with a family member in the U.S. or a sponsor as their immigration cases proceed.

NBC News and other media organizations have been denied access to the facilities where the unaccompanied children are being held. Requests for photos inside the facilities have also been denied.

Mayorkas said Sunday that his department would grant media access to Border Patrol facilities when it could do so in a safe manner under Covid-19 health protocols. The Trump administration allowed media access to facilities at the height of controversy surrounding its child separation policy in 2018.

After visiting a border facility, Sen. Chris Murphy, D-Conn., wrote on Twitter on Friday that he "fought back tears" talking to a 13-year-old girl who explained through a translator "how terrified she was, having been separated from her grandmother and without her parents."

Just left the border processing facility. 100s of kids packed into big open rooms. In a corner, I fought back tears as a 13 yr old girl sobbbed uncontrollably explaining thru a translator how terrified she was, having been separated from her grandmother and without her parents.

— Chris Murphy (@ChrisMurphyCT) March 19, 2021

Mayorkas, pressed to provide a time-frame for when the federal government would be able to have the border situation under control, declined to do so. He said that the goal was to be able to meet the 72-hour time limit as soon as possible.

"I have said repeatedly, from the very outset, that a Border Patrol station is no place for a child and that is why we are working around the clock to move those children out of the Border Patrol facilities, into the care and custody of the Department of Health and Human Services that shelters them," Mayorkas said.

There were 5,049 unaccompanied children in CBP custody as of Saturday, NBC News reported.

Mayorkas said that the Biden administration's approach was more humane than the one taken under Trump. Addressing Murphy's tweet, Mayorkas said that the 13-year-old girl would have been removed from the United States under the previous administration.

"We will not abandon our values and our principles. We will not abandon the needs of vulnerable children. That is what this is about," Mayorkas said.

In addition to challenges caused by the Trump administration, the DHS secretary also cited the Covid-19 crisis as a complicating factor.

"We are in the midst of a pandemic and that makes the operations that much more difficult," he said.

On each of the three networks he appeared on on Sunday, Mayorkas repeated that the border was "closed." He told migrants not to attempt to cross the U.S.-Mexico border at this time.

"We strongly urge — and the message is clear — not to do so now. I cannot overstate the perils of the journey that they take," Mayorkas said on NBC's "Meet the Press."

The situation at the border is complicating a push by Democrats for bipartisan immigration reform.

The House of Representatives passed two bills last week that would create a path to citizenship or legal status for millions of undocumented immigrants, but that legislation faces an uphill battle in the Senate.

A more ambitious comprehensive immigration reform package backed by the White House and introduced in Congress in February appears less likely to gain support.

Mayorkas was confirmed by the Senate on Feb. 2 by a vote of 56-43.

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