A Chicago nonprofit faces mounting criticism for the treatment of migrant children who were separated from their parents at the U.S. southern border under President Donald Trump’s “zero tolerance” crackdown on illegal immigration.

The Washington Post recently reported on allegations of abuse at Casa Guadalupe, a Chicago shelter run by the nonprofit Heartland Alliance, that included shelter employees making children scrub toilets with their bare hands. In another instance of alleged abuse, two boys told the newspaper that an employee gave injections to a 5-year-old to make him sleepy.

Here’s an quick explainer of what you need to know about the migrant children being held in the Chicago-area.

How many kids are being held in Chicago?

The Heartland Alliance said in June that it received 66 of the more than 2,500 children who have been separated from their parents, according to the Chicago Tribune.

But it’s unclear how many of those children currently remain at shelters run by Heartland. On Tuesday, Heartland officials declined to say how many migrant children are being held when pressed by Chicago aldermen during a public hearing.

A federal court gave the Trump administration until Thursday to reunite families, so it’s possible some of the 66 children at Heartland are with their parents, but we don’t know. This week, however, the Trump administration said in court filings that more than 450 parents have already been deported without their children, according to The Washington Post.

Some families have gone to the courts to get their children back. A federal judge in Chicago last month ordered the immediate release of a 9-year-old Brazilian boy, Diogo, who had been held at a Heartland Alliance shelter.

How are the allegations of abuse being handled?

Both state and federal authorities have opened investigations into the Heartland Alliance’s Casa Guadalupe shelter, The Washington Post reports, adding that officials at the nonprofit say they are working with investigators and have launched their own internal probe.

“We are investigating and are reviewing incident reports, medical records, staff disciplinary reports, examining our policies and protocols, and more,” the nonprofit said in a statement. “We welcome additional investigation of our programs, and if any investigation reveals that a staff member placed a child in danger, we will take immediate action.”

The Chicago City Council, meanwhile, is considering whether to license such shelters in response to the abuse allegations. Powerful Ald. Ed Burke, who faces criticism in this predominantly Latino 14th Ward because his law firm has represented Trump on tax-related issues, is pushing for child welfare agencies to be licensed with the city.

But some alderman say Burke’s proposal could create a bureaucratic nightmare for daycare providers. And it’s not entirely clear if the Heartland Alliance needs a city license, as it has permits with the state and federal government.

What is the Heartland Alliance?

The Heartland Alliance is a 130-year-old social service agency that provides housing and other programs to the underprivileged. Some of the services it provides include HIV prevention and counselling, housing and mental health support for refugees, and mental health and substance abuse help for the homeless, according to its website.

