A shocking crime has investigators in the Quad Cities looking for the killers of a teenage girl. A 16-year-old girl who works at a Davenport movie theatre is being held on a million dollars bond, charged with first-degree murder in the death of her friend. Prosecutors charge that Sarah Kolb and at least one companion killed 16-year-old Adrianne Reynolds in the parking lot of a Taco Bell restaurant in Moline one week ago. Investigators say they found the victim’s remains in Rock Island, at the Black Hawk State Historic Site, and say the body had been dismembered and someone also had tried to burn the remains. Authorities say the two girls knew each other from a school where both were working to earn their G-E-D’s. On Thursday they arrested 17-year-old Corey Gregory on two counts of first degree murder and one of concealing a murder, and say there may be more arrests in the case.