CHICAGO (CBS NEWS) — Three daycare workers who allegedly gave gummy bears that were laced with melatonin to a group of 2-year-old children to calm them down for nap time have been arrested, CBS Chicago reports. Police say the workers — identified as 32-year-old Kristen Lauletta, 19-year-old Jessica Heyse and 25-year-old Ashley Helfenbein — each face two counts of child endangerment and two counts of battery.

A manager at the Kiddie Junction Daycare Center told police one of the teachers had been distributing the laced gummy bears without authorization from parents.

“Allegedly, this was done in an effort to calm them down before nap time,” police said in a statement Monday.

The women told police they didn’t think what they did was inappropriate because melatonin is an over-the-counter sleep aid.

The parents of every child at the daycare center were notified of what happened.

The investigation is ongoing.