PITTSBURGH — A Pittsburgh police commander says detectives found no drugs when they searched the home of a kindergartner who brought heroin to school.

Cmdr. Maurita Bryant says police are still trying to determine the source of the 18 individual dose packets stamped “magic ticket” that the 7-year-old brought to Roosevelt Primary School on Wednesday. Pittsburgh Public Schools spokeswoman Ebony Pugh tells the Pittsburgh Tribune-Review that three families also notified officials when their children brought home heroin allegedly given to them by the boy.

Police spokeswoman Diane Richard said the boy didn’t know what the substance was, though Pugh says the boy believed the substance was “magic” because of the way it was packaged. Pugh says the boy will face unspecified school discipline.

Allegheny County child caseworkers are also investigating.