Biden officials still can't find the parents of 337 children separated at the Mexico border by the Trump administration, court docs show

• The Trump administration split hundreds of migrant children from their parents at the US border.
• The Justice Department and ACLU are slowly reuniting children with their parents or guardians.
• But they are still struggling to reunite some 337 children, court documents show.

US officials are struggling to locate the parents of more than 300 children who were separated at the US-Mexico border during the Trump era, court filings show.

To date, activists and US officials have helped reunited 861 children with their parents, but 337 still remain in limbo, according to a court filing Wednesday by the Justice Department and the American Civil Liberties Union.

In February, President Joe Biden signed an executive order that established a task force to address the issue and the number of children left without their parents has been slowly going down.

The Biden administration found that 3,913 children were separated from their parents as part of the Trump administration's "zero tolerance" policy at the US-Mexico border launched in 2018, CNN reported.

But that practice actually started in 2017, according to the ACLU, a year in which more than 1,000 families were separated.

The ACLU said in the Wednesday filing that the parents of 75 children are currently believed to be in the US, but that the parents of 250 children are no longer in the country.

Lawyers and authorities also do not have contact details for the parents, sponsor, or attorney of 12 children, the ACLU added.

On May 3, the Department of Homeland Security announced that the first set of families, separated by the Trump administration, were to be reunited.

Though the Biden administration is working to reunite families, it is also taking steps to discourage migrants from traveling to the US southern border.

"I can say quite clearly: Don't come," Biden told ABC in March.