These kinds of stories are always disturbing, especially to those who have kids. I can recall a couple things in the past that stood out in my mind.
1. There was a child prostitution ring in Rhode Island (maybe Connecticut) years ago that, when it was uncovered, had no adults involved. The ring was being run entirely by the kids. Apparently, when one of them was approached, and found that she could make money for favors, she told her friends. They had done the whole operation on their own.
2. One of my former supervisors told me that a couple of his classmates disappeared when he was in grade school. Years later, their names turned up on John Wayne Gacy's list.
3. In my old neighborhood in Illinois, we went to get the kids at the bus stop a block from home. With all of us there, a car pulled up and offered a ride to the neighbor girl because she was walking alone. She turned back towards us without hesitation. The old guy didn't realize (we think) that he was pointed down a dead-end road. We waited for him to drive back, and then called the police.