Homeland Security Secretary Alejandro Mayorkas repeatedly argued on Sunday that the United States’ border with Mexico is “closed,” amid a marked increase in immigrant arrivals, particularly of unaccompanied minors.

Reports emerged Sunday that the administration has at least 15,500 unaccompanied minors in custody — 10,500 in the care of the Department of Health and Human Services (HHS), and 5,000 detained by US Customs and Border Patrol (CBP).

The minors being held by HHS are being housed in emergency shelters and facilities licensed for child care, according to CBS News, while the roughly 5,000 children and teenagers in CBP care are being kept in crowded, “jail-like facilities,” according to a CNN report that cites case managers, lawyers, and law enforcement.

That report describes a setting in which “children are alternating schedules to make space for one another in confined facilities, some kids haven’t seen sunlight in days, and others are taking turns showering, often going days without one.”