WASHINGTON (Reuters) - The U.S. government still has 2,053 children in its custody who were separated from their parents under President Donald Trump’s “zero tolerance” immigration policy and officials said there was a “well coordinated” process for reuniting families.

Migrant children make their way inside a building at Casa Presidente, an immigrant shelter for unaccompanied minors, in Brownsville, Texas, U.S., June 23, 2018. REUTERS/Loren Elliott

The Department of Homeland Security issued a fact sheet late on Saturday in the face of criticism from lawyers for parents and children who have said they have seen little evidence of an organized system.

A total of 522 children in the custody of U.S. border officials have already been reunited with parents, according to the fact sheet, which was published three days after Trump ended his policy of separating families on the U.S.-Mexico border.

Trump’s shift came after images of youngsters in cages triggered outrage at home and abroad.

On Sunday, Trump renewed his hardline on immigration calling for people who enter the United States illegally to be sent back to where they came from immediately without any judicial process.

An administration official said on Sunday 522 children were able to be reunited because their parents came back from court proceedings quickly enough that the children had not yet been transferred to the custody of the Department of Health and Human Services, where the more than 2,000 children who remain separated from their parents are now.

“The United States government knows the location of all children in its custody and is working to reunite them with their families,” the DHS fact sheet said.

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The new details came after more than two months of confusion how detained migrant parents, who are shuttled from facility to facility run by different government agencies, would ever reunite with their children, who are sent to shelters and foster homes scattered across the country.

The DHS said the Trump administration has a process for how parents would be reunited with their children “for the purposes of removal,” or deportation.

Deportation proceedings could take months to complete, and the fact sheet did not say whether parents and children would be reunited in the intervening time.

PHONE CALLS

The Port Isabel detention center in Texas will serve as “the primary family reunification and removal center” for adults in ICE custody, the statement said.

Many of the parents are planning to claim asylum, lawyers and advocates who have spoken with them said. The fact sheet did not say how reunifications would be handled in those cases.

The fact sheet said children are given the chance to speak with a “vetted parent, guardian or relative” within 24 hours of arriving at a facility run by Department of Health and Human Services.

Sirine Shebaya, a senior staff attorney with Muslim Advocates, said she and two other lawyers met about 70 detained Central American migrants at Port Isabel on Friday and Saturday. All but one had been separated from their children, she added in an interview before the fact sheet was published.

Several of the migrants had been given a number to call to try to locate their children, but found their calls would not go through or no one picked up, she said. If they did manage to get someone on the line, they were often told they would get a call back – useless to them while in a detention center.

“When they do get a phone call, it’s a one- to two-minute phone call and the kids frequently don’t know where they are,” she said. “Some kids know, ‘OK I’m in Michigan,’ but they don’t know any more than that.”