A video obtained by ProPublica shows the Border Patrol held a sick teen in a concrete cell without proper medical attention and did not discover his body until his cellmate alerted guards. The video doesn’t match the Border Patrol's account of his death. Customs and Border Protectionsaid that an agent had found Carlos “unresponsive” after checking in on him. ProPublica has obtained video that documents the 16-year-old’s last hours, and it shows that Border Patrol agents and health care workers at the Weslaco holding facility missed increasingly obvious signs that his condition was perilous. “Why is a teenaged boy in a jail facility at all if he is sick with a transmissible illness? Why isn’t he at a hospital or at a home or clinic where he can get a warm bed, fluids, supervised attention and medical care? He is not a criminal,” said Dr. Judy Melinek, a San Francisco-based forensic pathologist who reviewed records of Carlos’ death at the request of ProPublica. Interviews and documents illustrate how immigration and child welfare agencies, while grappling with surging migrant numbers, were unable to meet their own guidelines for processing and caring for children. With holding tanks that were never equipped to house migrants for more than a few hours, the Border Patrol was inundated with families and children. Shelters for children, offering beds and medical care, were already packed. Migrants were supposed to be held in CBP centers for no more than three days before being deported, moved to Immigration and Customs Enforcement detention centers or released pending a hearing. But Carlos had arrived at the peak of the surge, with 144,000 migrants apprehended in May alone. With the overflow crowds, nothing was working as it should have been. HHS and Immigration and Customs Enforcement were backlogged in transferring children out of CBP custody. In a spot check soon after Carlos died, the DHS inspector general reported that a third of the 2,800 unaccompanied minors in CBP custody in the Rio Grande Valley had been there longer than 72 hours.