SAN DIEGO (CN) – The federal government likely separated an additional 1,250 immigrant children from their parents at the U.S.-Mexico border before formally announcing its “zero tolerance” immigration policy, a Health and Human Services official told a federal judge Friday.

Health and Human Services Cmdr. Jonathan White told U.S. District Judge Dana Sabraw he believes a “final accounting” would show at least 1,250 additional kids have been separated from their parents before Sabraw issued an injunction stopping the family separation practice.

The additional separations will likely be confirmed before an Oct. 25 deadline set by Sabraw in the expanded family separation class action he’s presiding over in the Southern District of California.

The government had 6 months to account for all additional families it separated after a report by the Office of Inspector General this past January raised the alarm that thousands more children may have been separated than previously thought.

The American Civil Liberties Union also alerted the court this summer about hundreds more families that have been separated despite Sabraw’s order ceasing the practice. The government had separated those families due to parental criminal history for minor crimes including misdemeanors.

The ACLU has asked Sabraw to find those separations violate his preliminary injunction order, but the judge has not yet ruled on the matter. He indicated Friday he expects to issue a decision within a couple weeks.

White said Friday the review process for 11 different data sets cross-referenced by several immigration agencies would be completed within a week.

Sabraw noted the process of reuniting the newly separated families is likely to be more arduous than the first time around.

Steven Herzog – who heads the steering committee of law firms and nonprofits working to reunite separated families – confirmed most of the parents have been deported to Guatemala and Honduras.

“It’s going to be more challenging to track them down than the initial group of 471 parents who were deported without their kids,” Sabraw said.

Herzog said a group of nearly 100 attorneys have made more than 4,200 phone calls to parents and sponsors in their reunification efforts for the 868 children of possible new class members that have so far been identified.

About 436 sponsors and 225 parents have been reached.

Only 23 parents have been located in their countries of origin so far, Herzog said.

ACLU attorney Lee Gelernt said they will likely need governmental assistance this time around to locate all the parents who have been deported.

“There needs to be a conversation of whether there is anything the government can do to help the process given what we’re looking at. I think we are going to need more resources,” Gelernt said.

A status conference in the case is scheduled for Nov. 8.