(CNN) A federal judge has blasted a declaration from a senior official at the Department of Health and Human Services who claimed that using a streamlined approach for reuniting children with their parents separated at the border could place the kids in danger.

"Unfortunately, HHS appears to be operating in a vacuum, entirely divorced from the undisputed circumstances of the case," San Diego-based Judge Dana Sabraw wrote in an order after the HHS declaration was filed late Friday.

In a radical departure from his typical tone to date, the judge -- a George W. Bush appointee -- went on to suggest the department's filing was an attempt to "provide cover to Defendants for their own conduct in the practice of family separation, and the lack of foresight and infrastructure necessary to remedy the harms caused by that practice."

After Friday's dust-up, Sabraw ordered the government to have an HHS representative in the court hearing Monday in addition to the usual Justice Department attorney.

The declaration Friday from Deputy Assistant Secretary for Preparedness and Response Chris Meekins said, "I recognize that the likely result of implementing the Court's order through the inter-departmental reunification plan will be faster reunifications of a significant number of children with their parents. At the same time, however that process will likely result in the placing of children with adults who falsely claimed to be their parents or into potentially abusive environments. While I am fully committed to comply with this Court's order, I do not believe that the placing of children into such situations is consistent with the mission of HHS or my core values."

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