The American Civil Liberties Union of Illinois on Friday took the state’s child welfare agency to federal court to attempt to force the removal of all children in its care from a troubled Chicago psychiatric hospital after additional claims of sexual abuse there.

A sexual assault allegation involving a 19-year-old patient, cited in the ACLU’s emergency court filing, comes as Aurora Chicago Lakeshore Hospital faces intense scrutiny following a string of disturbing accusations of sexual and physical abuse. The Illinois Department of Children and Family Services sends hundreds of children to the hospital each year, relying on Lakeshore to treat those with severe mental illness who are sometimes turned away by other hospitals.

DCFS acknowledged Friday that it is also investigating a separate sexual abuse allegation, called into the state’s hotline Wednesday, involving two patients, a 14-year-old male and a 16-year-old transgender female, fondling each other at the hospital, according to a source with knowledge of the report. The girl, who is the subject of a previous abuse allegation at Lakeshore, came to the U.S. as an unaccompanied minor from Honduras and is in the custody of the federal government, records show.

That brings the number of DCFS investigations into accusations of abuse or neglect at the hospital to 18 since January. The agency has found evidence to support four of those allegations, while seven were found to be unsubstantiated. Seven cases, including the two most recent reports, remain under investigation.

The new abuse allegations come after a series of moves designed to increase oversight at the facility following a ProPublica Illinois investigation late last month that revealed problems at Lakeshore, including the allegations that children had been raped or sexually abused by patients and staff and that federal regulators have threatened to pull the hospital’s funding over safety concerns. The Chicago Tribune published a separate investigation into the allegations.

“It only confirms the very deep fear that we have that there was inadequate supervision of youth at the hospital, and the time has passed to try to fix that problem,” ACLU general counsel Heidi Dalenberg said. “The only safe thing to do at this point is to remove the children. We can’t trust DCFS to monitor the safety of these kids.”

In response, DCFS said in court filings that it will provide round-the-clock supervision starting at 8 a.m. Saturday of children in its care at Lakeshore and that it “continues to work proactively” to move them out of the hospital.

“Although we don’t know all of the facts regarding these incidents, we are increasing our staff presence at the hospital to provide additional supervision of the safety and care of DCFS youth,” said Neil Skene, special assistant to DCFS Acting Director Beverly “B.J.” Walker.

More than 240 children and young adults in DCFS care have been admitted to the hospital this year. As of Friday, the agency said 13 remain, including two who are scheduled to be released Monday and six who have been cleared for discharge but cannot leave the hospital because the agency has not found them a place to go.

This has been an ongoing problem for the agency, as documented in a June ProPublica Illinois investigation that found hundreds of children languish in psychiatric hospitals beyond what is deemed medically necessary.

At an emergency hearing in front of U.S. District Judge Jorge Alonso on Friday afternoon, DCFS and the ACLU could not agree on who should approve the transfers of the remaining children in the department’s care at Lakeshore.

The ACLU, which monitors DCFS as part of a decades-old federal court consent decree, asked that a court-appointed expert and doctors from the University of Illinois at Chicago Psychiatry Department supervise and approve the transfers. The agency, according to its lawyers, does not want to cede that approval to someone outside DCFS.

ACLU attorneys noted that DCFS previously contracted with UIC to provide independent monitoring of psychiatric hospitals that treat DCFS children, but the department has moved away from outside oversight.

“The recent disclosures at the Hospital demonstrate the abject failure of that approach — indeed, the Department recently confirmed to Plaintiffs that it has no monitoring reports for Lakeshore for at least the last two years,” the filing states.

The two sides are expected to negotiate through the weekend and return to court early next week. They also must determine what to do if older youths in DCFS care check into the hospital on their own or if DCFS takes custody of a child already at the hospital.

Under growing pressure from the ACLU, lawmakers and child welfare advocates, DCFS agreed this month to stop sending children to the hospital; to permit an independent review involving children in its care at the facility; and to prioritize moving out children held at the hospital beyond what is deemed medically necessary.

The sexual assault allegation involving the 19-year-old occurred during the last week “despite the fact that DCFS has been making daily visits to check on youth at Lakeshore, and despite the fact that Lakeshore’s operations currently are under investigation by state and federal authorities,” ACLU attorneys wrote in the filing.

The young woman was transferred to another hospital for an evaluation after she made the allegation. A DCFS worker wrote that the woman still needed to “work through her disclosure” and the agency hadn’t determined if it rose to the level of an investigation, records show. ACLU attorneys objected to this assessment.

“It should always be investigated,” ACLU attorney Claire Stewart said.

No details about the alleged assault were available, but the court filing said there was evidence to show the woman had been previously sexually abused and had a history of more than 25 psychiatric hospitalizations at 10 different hospitals.

The report involving the two teens alleges that they fondled each other this month under a blanket in a the day room while a staff member was present, according to a source with knowledge of the allegation. DCFS is investigating the hospital over inadequate supervision.

Among the four substantiated cases of abuse are a report that a 17-year-old boy fondled a 12-year-old boy and tried to inappropriately touch several other patients, according to confidential records obtained by ProPublica Illinois. In another substantiated incident, a 17-year-old boy said workers dragged him to his room, pinned him down and left him with bruises and a bloody mouth, records show. DCFS is investigating another allegation involving the 16-year-old transgender girl who was the subject of the hotline call this week. She also reported that she had sex with another patient at the hospital last summer.

Skene said DCFS has assigned one administrator to oversee all pending investigations at Lakeshore “to ensure consistency and to help us go beyond individual incidents and explore any patterns that cause concern for the safety of youth at the hospital.”

In an email Friday, Lakeshore Hospital CEO David Fletcher-Janzen said the hospital provides “the best care to the most vulnerable people.” Hospital officials did not respond to allegations involving individual patients.

“We want to help increase access to vital mental health care services throughout Illinois,” he said.

Under the threat of court action this month, DCFS agreed to provide reports to the ACLU and a court-appointed expert within 24 hours of its daily visits to the hospital. The allegation involving the 19-year-old surfaced in one of those reports. But Dalenberg criticized the agency for not immediately notifying the ACLU of the allegation.

The Cook County acting public guardian, Charles Golbert, who appeared at Friday’s hearing, said the overarching concern is the department’s lack of placements for children who need them, particularly those who are trapped in psychiatric hospitals after they have been cleared for release. DCFS signed the consent decree 27 years ago, he said, and by doing so made a promise to create the services and placements for children in its care.

“It’s been decades,” Golbert said. “And kids are still waiting.”