? A popular Nutley High School senior is behind bars because police say she was the leader of a drug ring.

Police arrested 18-year-old Stephanie Klotz, who is described as a good student and athlete with plenty of friends, on Friday as part of operation ?Clean Sweep.? Authorities say they discovered Klotz dealing marijuana out of a parking lot during their three-month investigation. They say she made up to $700 a week and may have used juveniles in her operation. Police made 12 other arrests and expect to make a dozen more.

Parents, students and school officials say they are shocked that the illegal activity was taking place in their small town.