Edgard Garrido/Garrido Members of migrant caravan walk next to the border fence between Mexico and the US before preparations for an asylum request in the US, in Tijuana.

Hundreds of children have been separated from their parents at the US-Mexico border under the Trump administration’s new “zero-tolerance” policy toward people who illegally cross the border.

Those children, who are placed in foster care or in government shelters while their parents are detained, have been suffering from trauma, according to foster-care families and workers.

The Trump administration has been using the family separation practice as a deterrent for would-be migrants seeking to illegally enter the US, though the amount of border-crossing arrests appears unaffected so far.

The children who have been separated from their parents at the US-Mexico border due to the Trump administration’s new “zero-tolerance” policy are already suffering severe anguish and trauma, the families and non-profit workers involved in the foster-care process say.

In May, the Trump administration announced it would criminally prosecute each person caught crossing the border illegally – a move that splits them from their children, sending them into foster care or government shelters.

One such child is José, a five-year-old boy from Honduras who last saw his father when he was arrested and led away at the US border in El Paso, The New York Times reported.

José’s foster mother, Janice, told The Times that the child arrived with nothing but a trash bag full of dirty clothes, and two small drawings he called “photos.” One was a stick-figure sketch of his family back in Honduras, and the other was a drawing of his father.

The agony of separation: A five year old Honduran boy separated from his dad at border. This is the picture he holds onto. Please read my story. https://t.co/ykav2zvwGP pic.twitter.com/nwp6oirgR4 — Miriam Jordan (@mirjordan) June 7, 2018

“He holds onto the two pictures for dear life,” Janice told The Times. “It’s heart-wrenching.”

Janice told the newspaper that José asks in Spanish every day, “When will I see my papa?” and she always replies that she doesn’t know.

She added that she and her family have frequently taken in migrant children temporarily – until José, all of them had arrived in the US unaccompanied and only stayed with her family for several weeks or months. But they always had regular access to their parents through phone or video calls.

But in José’s case, he had no access to his parents until early this week, according to The Times. He spoke with both his mother and father in separate phone calls – and the realisation that he didn’t know when he would see them again “triggered all the separation trauma again,” Janice said.

It’s unclear exactly how many children like José have been separated from their parents in total, but a Customs and Border Protection official told lawmakers at a recent hearing that 658 children were separated from 638 adults just within the period of May 6 to May 19.

The Trump administration has faced significant backlash from the public over its family separation practice, but officials have staunchly defended the zero-tolerance policy as necessary in deterring illegal border-crossing, which has surged in recent months compared to last year’s record lows.

“If you cross the southwest border unlawfully, then we will prosecute you … If you are smuggling a child, then we will prosecute you and that child will be separated from you as required by law,” Attorney General Jeff Sessions said in early May. “If you don’t like that, then don’t smuggle children over our border.”

Though the policy was only implemented recently, it hasn’t appeared to have an immediate effect on the amount of border-crossing arrests. The Customs and Border Protection agency announced this week that its officers made more than 50,000 arrests in May – higher than in March and April.

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