As President Trump instructs the Immigration and Customs agency (ICE) this weekend to round up undocumented immigrants in major U.S. cities, lawyers and doctors claim that 250 young migrant children are living in dire conditions in a border facility on the U.S.-Mexico border.

The lawyers and doctors say that there is a lack of water, food and proper sanitation for the children at the Clint Border Patrol Station, which is located near the Texas border city of El Paso. CBS News reports that apprehensions of the migrants at the El Paso border area shot up over 600% since last year.

Clara Long, a researcher at watchdog Human Rights Watch (HRW), is one of the individuals monitoring the conditions at the border facility.

"The three-year old before me had matted hair, a hacking cough, muddy pants and eyes that fluttered close with fatigue," she wrote on HRW's website Friday. "His only caretaker for the last three weeks in a United States border patrol chain-link cage and then a cell … his 11-year old brother."

The children had crossed the border in May with their 18-year-old uncle, according to Long. Typically, children can only be detained by border patrol for a period of up to 72 hours but Long said some of these children had been at Clint for three to four weeks.

The Trump administration has come under fire by human rights advocates for its policies on the separation of migrant families at the U.S. border. Earlier this week, protestors demonstrated in front of the United Nations in Geneva with shirts that had the phrase #classroomsnotcages.

Trump blamed the Obama administration for the separations in an interview with Time Magazine. But while the Obama administration did engage in some separations, they were not a systematic policy like it has been under Trump's zero-tolerance rule.

Immigration was one of the main policy issues of Trump's 2016 presidential campaign. He famously said that he believes Mexican immigrants bring crime and drugs to the U.S.

Trump has frequently antagonized so-called "sanctuary cities," where migrants are shielded from ICE by local authorities and has tried to deny federal funding to those cities. District courts have denied such a request.