A report says more than 200 children who'd been flagged to the Illinois Department of Children and Family Services were killed over an 11-year period.
The report used records from police, prison and the medical examiner to look at deaths from 2000 to 2011.
The agency's Office of Inspector General investigates the deaths.
In many cases, calls had been made to the agency's abuse hotline. Sometimes, agency workers made mistakes or failed to act quickly. The agency's inspector general says in one case a worker lied about creating a safety play.
DCFS Director Richard Calica says the deaths are disturbing but resources are limited.
The state is making big budget cuts and case workers are overwhelmed.