CHICAGO (AP) — More people arrested on drug charges are alleging that a former Chicago Police sergeant convicted on corruption charges framed them.

The Chicago Tribune reports that this week a petition filed on behalf of 15 people asking that their drug convictions be overturned because they contend they were framed by former Sgt. Ronald Watts.

The petition is the latest chapter in a scandal that's resulted in Watts' 2013 conviction for extortion and the overturning of five convictions of people arrested by Watts and his crew. Also, two officers who alleged they were blackballed for trying to expose Watts' corruption settled their whistleblower lawsuit for $2 million.

The Cook County State's Attorney's office is reviewing other cases involving Watts to determine if he was involved in more tainted investigations.