Ameen Hurst, 20, entered guilty pleas to four counts of third-degree murder earlier this month.
Prosecutors say his spree of violence began when he was 16.
Authorities say he killed 20-year-old Dyewou Scruggs as he was walking to catch the bus on December 24, 2020 in Overbrook.
Less than a year later, Hurst killed 24-year-old Naquan Smith and 17-year-old Tamir Brown in Overbrook. Two others were wounded in the attack.
About a week after the double murder, authorities say Hurst gunned down 20-year-old Rodney Hargrove as he was released from Curran-Fromhold Correctional Facility (CFCF). Hargrove was not the target, however, according to the district attorney's office.
Hurst was arrested in April 2021, but two years later in May 2023, he and another inmate escaped from the Philadelphia Industrial Correctional Center, sparking a citywide manhunt. He was arrested 10 days later.
"It is hard to overstate the threat to public safety that this reckless and dangerous defendant posed to our city," said DA Larry Krasner.
The families of the victims were at a press conference with the district attorney on Thursday.
"I miss my grandson. I think I would never stop missing him...I would love to see [Hurst ] rot in hell," said Rodney's grandfather, John Hargrove Jr.