PHOTOS: See inside the tent city where migrant children are held after being separated from their parents at the US-Mexico border

More than 2,000 children were separated from their parents in the first six weeks of the policy, according to official figures.

Backlash against the policy has grown, fueled by audio leaked from another detention centre featuring children screaming and crying for their parents.

Aerial photos show kids walking through the newly formed tent city. Protesters gathered outside the facility on Sunday, calling for an end to the policy that separates the children from their families.

Journalists have not been granted access to the facility.

Children play soccer at the newly created encampment.

President Trump reportedly has begun to realise that children in the encampments are suffering but he doesn't want to back down and reverse the policy for fear of looking weak.

Instead, he wants Congress to craft new legislation ending the practice.

The tent city dormitories have bunk beds, handouts from Department Health and Human Services show.

These are the medical facilities.

Republican Representative Will Hurd toured the facility, telling Texas Monthly that the facility is "being run by emergency management professionals that have been in probably every disaster you can name in the past decade." But he said that the facility would not exist without the policies of the Trump administration.

Babies and toddlers under age 5 have been separated from their parents too, at three "tender age" shelters in South Texas, the Associated Press reports.

Children are processed through this intake room.

Congressional Republicans have been scrambling to craft legislation as global outrage grows against the policy.

Eleven states have pulled their National Guard troops from the Mexican border in protest over the camps.

Homeland Security secretary Kirstjen Nielsen was heckled by protesters as she ate at a Mexican restaurant in Washington, DC, last night.

While the kids are being held in these tents, their parents are being prosecuted as criminals.

The government's intent is to place the children with relatives, reunite them with their parents if they have legal status, or deport them.

This is a dining area.

Some parents will be deported without their children. It's not clear what the fate of the kids who remain in US detention will be.