The authorities in Texas have granted a child care license to a federal immigration detention center where thousands of mothers with their children have been confined, often for weeks and sometimes months.

The decision to recognize the center, in Karnes City, as a care provider for children drew outrage from immigrant advocates, who said it was little more than a prison. It was a victory for the Department of Homeland Security, which considers the center a holding station where families pass initial health and security checks and the first phases of their asylum screenings.

The Texas license strengthens the hand of the Obama administration as it tries to maneuver around a ruling from a federal judge in California, who ordered the rapid release of all migrant children and their parents and ruled that minors could not be held in secure facilities not licensed specifically for child care.

Officials at the Texas Department of Family and Protective Services did not make a statement about the license, which was issued on Friday and posted on the agency’s website early on Monday. The initial license is temporary, lasting six months.