The tip we received was unambiguous: Three children had run away from a shelter for immigrant children on Chicago’s North Side in late August.

But in a system shrouded in secrecy, trying to confirm even straightforward tips is complicated. We know this from our ongoing reporting, including our most recent story this week, about the network of nine shelters in the Chicago area that house immigrant children and are run by Heartland Human Care Services.

Although we didn’t want the children’s names or any personal information — just confirmation the incident had or hadn’t occurred — Heartland wouldn’t tell us anything, citing federal guidelines and the children’s privacy.

There are legitimate reasons to keep certain information about these children confidential. Some of them have fled dangerous situations, like gang attacks and sex trafficking, that could follow them here; others have experienced trauma that should be dealt with privately. Those are among the reasons we don’t typically use their last names. But other aspects of this issue, one that has drawn intense national attention, ardent debate and raised questions about how tax dollars are being spent, merit public scrutiny.

In this one incident lies a much larger truth: The children within this system live behind walls, both literally and figuratively, and their stories and experiences remain virtually unknown.

That’s why the story we published this week is so unusual. Much of our reporting drew upon thousands of internal documents on the children, including records of their troubles both before and after entering federal custody, how many months they were inside and descriptions of the difficulties they faced. None of this had been publicly known before.

While Heartland officials wouldn’t confirm the runaway tip, they did tell us it is “uncommon” for children to run away from their shelters, though as we previously reported, at least 10 children ran away while in Heartland’s care from December 2014 to 2017, including seven from the Rogers Park facility, where the tipster said the most recent incident occurred.

We called a number of current Heartland employees who have reached out to share information with us about what happens inside the shelters. No one we spoke to could corroborate the tip, although one employee described an unannounced alarm and head count last week, “like if something happened.”

But we got the tip confirmed in two other ways. A Chicago Police Department spokesman told us officers responded to a missing persons call on the block where the Heartland shelter is located. Two 17-year-old boys and a 16-year-old boy were reported missing on Aug. 26, the spokesman said.

Not only that, they are still missing.

The Illinois Department of Children and Family Services, which licenses Heartland’s facilities and investigates allegations of abuse and neglect, told us they have opened an investigation into the missing boys.

We will keep reporting, on this and other questions about what is happening to the immigrant children housed here. We plan to publish another story next week.

If you or anyone you know works in the detention system for immigrant minors, please contact us. You can also send documents confidentially to us:

• Melissa Sanchez: 872-444-0011 (Signal) or Melissa.Sanchez@propublica.org
• Jodi S. Cohen: 312-731-8867 (Signal) or Jodi.Cohen@propublica.org
• Duaa Eldeib: 312-730-4797 (Signal) or Duaa.Eldeib@propublica.org

Thanks for reading — and sharing what you know.

—Melissa, Jodi and Duaa