Separated into groups by walls of plastic sheeting, dozens of migrants lie on the floor, packed closely in together in recent photographs taken inside a US border processing center in Donna, Texas.
The photos were released on Monday and were provided to Reuters by Texas Democratic Representative Henry Cuellar, whose office said they were taken over the weekend.
In one of the first major challenges of his presidency, US President Joe Biden is trying to contain a burgeoning humanitarian crisis along the southwest US border with Mexico.
A sharp rise in the number of migrants fleeing violence, natural disasters, and economic hardship in Central America is testing Biden's commitment to a more humane immigration policy than that of his predecessor, Donald Trump. Hopes of a less hardline response from the US government has encouraged some migrants to make the journey north.
US officials are struggling to house and process an increasing number of unaccompanied children, many of whom have been stuck in border stations for days while they await placement in overwhelmed government-run shelters.
The US Customs and Border Protection (CBP) said last month it was opening the temporary facility in Donna to provide processing capacity for the heavily trafficked Rio Grande Valley sector while a permanent center in McAllen was being renovated. It said at the time that the Donna facility was expected to provide ample areas for eating and sleeping.
In one photo, people of all ages, including children, are shown sitting on the floor. With the coronavirus pandemic still raging, all appear to be wearing masks but they are crowded close together.
In others, rows of people are seen lying down next to each other on mats and covered in emergency blankets.
The Centers for Disease Control and Prevention guidelines for physical distancing during the pandemic is at least 6 ft to reduce the spread of the coronavirus.
The CBP did not immediately reply to a request for comment.