Arshad Curry was convicted for the homicide of Kaylen "KJ" Johnson, a student-athlete from Boys Latin Charter School, at 56th and Vine streets in July 2021.
Johnson and 18-year-old Tommie Frazier, who attended Simon Gratz High School Mastery Charter, were on their way to basketball practice, Krasner said.
That's when Curry opened fire on their vehicle.
Johnson and Frazier were both killed in the shooting and a third teen was injured.
Krasner said the group was not Curry's intended target.
Investigators say Curry was also responsible for the murder of another teenager a few months later in Port Richmond.
He was arrested after opening fire on two police officers who responded to the scene. The officers were not injured.