More than 450 migrant parents who were separated from their children at the southern U.S. border are no longer in the United States though their children remain in the country, according to a joint filing by the federal government and American Civil Liberties Union.
The 463 missing parents are believed to have been deported, according to the filing as reported by Reuters.
Their absence could hamper government efforts to reunite separated families by Thursday, the deadline the Trump administration has been given to reunite the thousands of families separated under its "zero tolerance" separation policy.
The ACLU is concerned that parents might have been deported without understanding their options.
“These parents urgently need consultations with lawyers, so that they do not mistakenly strand their children in the United States,” the ACLU wrote in the court filing, according to Reuters.
The ACLU said it also had not been given a list of the parents who had signed a form in which they had "volunteered" to be deported without their children.
There have been concerns over reports that U.S. Immigration and Customs Enforcement agents had been pressuring detained immigrant parents separated from their children to sign voluntary deportation forms under the impression that it would be the only way for them to see their children again.
ICE has maintained that while it had been using such a form detailing parents' options on leaving the U.S. with or without their children, it was used only in cases where parents were subject to a final order of deportation as part of a "long-standing policy."
San Diego District Judge Dana Sabraw gave the federal government until July 26 to reunify all of the children who were separated from their parents under the Trump administration’s “zero-tolerance” immigration policy — which ended up a total of about 2,500 children.