HOUSTON (AP) — The U.S. government said Wednesday that it should not have to automatically release immigrant parents detained with their children — including some infants — after a federal judge set a deadline for the children to be freed, which advocates warned could lead to the renewed separation of families.

In court papers, the Trump administration argued Judge Dolly Gee’s findings on Friday were “insufficient” to prove the allegations made by families that U.S. Immigration and Customs Enforcement isn’t doing enough to control the spread of coronavirus, even as there have been confirmed cases of COVID-19 in two of three family detention centers in Texas and Pennsylvania.

Gee set a July 17 deadline for the U.S. to release children held longer than 20 days in family detention, either by freeing them with their parents or placing them with sponsors. Gee described the centers as being “on fire.”

Lawyers for the detained families said they are worried that U.S. Immigration and Customs Enforcement will continue to detain families together or push parents to allow their children to be freed without them.

Together, the three facilities currently detain 138 parents and 139 children.

Gee’s order did not apply to the parents detained with their children, some in rooms where they aren’t allowed to see other people and fear that infected staff members have given them the virus. One mother told The Associated Press that her 8-year-old son was denied toys until just before a group of congressmen visited, an allegation that ICE denied. Eighty congressmen signed a letter Tuesday calling on ICE to release families together.

A group of parents and children held in family detention centers separately sued the U.S. earlier this year in federal court in Washington. The families allege the conditions of their detention violate the U.S. Constitution. Judge James Boasberg, who oversees that case, had asked lawyers for both sides to explain how Gee’s order applied to the case before him.

The government said Wednesday that it was still working on a plan to comply with Gee’s order. But it argued that the “remedy for a constitutional violation of condition of confinement is to remedy the violation, not to release petitioners,” referring to the families that sued. Boasberg should not order detained families to be released, the U.S. said.

Lawyers for the families accused the U.S. of presenting parents with a “Hobson’s choice” to relinquish their children or keeping them in detention centers “where their risk of coronavirus infection is dramatically heightened.”

 “Everyone’s got their fingers crossed and hope that ICE is listening to the American public who doesn’t want family separation,” said Andrea Meza, director of family detention services at the legal group RAICES. “It makes no logical sense why they’re hanging on to these people.”

At least 11 parents and children have tested positive for COVID-19 at the detention center in Karnes City, Texas, and several employees have tested positive at both Karnes and the facility in nearby Dilley. The government said Wednesday that there have been no positive cases at the Berks County detention center in Pennsylvania.

Fewer than 1,000 children are in the U.S. Department of Health and Human Services’ system of facilities for unaccompanied minors.

Those figures have dropped sharply from last year, when reports of fetid conditions at some overcrowded border facilities sparked outrage. Most border crossers are now being expelled under an emergency order citing the need to stop the spread of the coronavirus, even though the U.S. has by far the most confirmed virus cases of any country. At least 2,000 children have been expelled under the order.