DHS Secretary Mayorkas to visit border amid controversy over migrant surge

Department of Homeland Security Secretary Alejandro Mayorkas was headed to visit the southern border Friday amid growing controversy over how the Biden administration is dealing with a surge in migrants, especially unaccompanied children.

Mayorkas is making his second trip as secretary to El Paso, Texas, "to view operations and receive a briefing on the processing, shelter, and transfer of unaccompanied children arriving at our border," DHS said.

The trip is closed to the press and members of the public due to COVID-19 restrictions and privacy concerns, the agency said.

The Democratic chairman and top Republican on Senate Homeland Security Committee are expected to travel with Mayorkas to the border, sources familiar with the plans and a spokeswoman for Sen. Rob Portman, R-Ohio, told ABC News.

In addition to Portman and chairman Gary Peters, D-Mich., two other senators were expected to be part of the delegation as well.

On "CBS This Morning" Thursday, Mayorkas was pressed on what conditions are like inside the Customs and Border Protection facilities where children are held -– one of which he said he has he toured.

"It's crowded, and remember we're dealing with a pandemic, and so we're dealing with restrictions on physical distancing and the like. But the mattresses, the blankets are actually selectively chosen so that they're safest for the children," Mayorkas said. "So actually the equipment, the provisions that we give to these children are selectively chosen for their care. But I have to repeat because I don't mean to walk away from this, the border patrol station is not a place for children."

No media nor the public has seen the conditions inside CBP or HHS facilities firsthand.

In a statement to ABC News, U.S. Customs and Border Protection said whether to allow access to facilities is evaluated on a case-by-case basis.

"Since March 2020, CBP has discouraged external visitors in CBP facilities, including media ride-alongs, due to agency COVID protocols and in order to protect the health and safety of our workforce and those in our care," the agency said. "We are offering and utilizing outdoor interviews or virtual operational briefings."

Mayorkas said DHS is working with the Department of Health and Human Services to quickly set up more facilities to house children.

He reiterated his message to migrants: Do not come to the United States now.

"It's do not come because it is not safe to take the journey, it is not safe in a time of pandemic to arrive at the border. Families and single adults are being expelled. Let us build, let us rebuild," he said.

ABC News' Trish Turner and Katherine Faulders contributed to this report.