Gregory Jackson, 34, Alexis Quinn, 27, and 22-year-old Kris Minners, all of whom were pronounced dead at local hospitals.
Jackson was identified by those who know him as a boxer, "vital as ever," whose name in the ring was "Japan Jackson."
Minners was a graduate of Girard College, where he had been working as a residential advisor for 6th and 2nd grade boys, the school said in a statement.
"Kristopher was so proud to return to Girard and serve as a role model to the young boys in his care," Interim President James D. Turner said.
"He was doing an amazing job for us, even being named RA of the month in March. Kris was a vital member of our community, and his loss will be felt deeply."
Quinn was being remembered as her mom's "little twin."
City officers assigned to a foot detail heard gunshots coming from the area of 400 South Street around 11:30 p.m. They ran over and saw several civilians lying on the sidewalk and street with gunshot wounds, authorities said.
As the officers began rendering first aid, one noticed a black male on the southwest corner of South and American Streets firing a handgun into a large crowd. He drew his weapon and fired several times in the direction of the unknown male, who dropped his handgun on the sidewalk and ran southbound on 600 American Street. He was lost in the area.
The discharging officer is a 3.5-year veteran of the Philadelphia Police Department assigned to the 18th District. As per protocol, he has been placed on administrative duty pending the outcome of the OISI and Internal Affairs investigations.
Mayor Jim Kenney released a statement calling the incident "beyond devastating."
"Once again, we see lives lost and people injured in yet another horrendous, brazen and despicable act of gun violence," he said. "My heart is with the family, friends, and loved ones of those lost or injured, and with everyone impacted by this terrible tragedy.
Philadelphia Police Department is investigating the "heinous crime" to ensure the people who are responsible are brought to justice, the mayor said.
Anyone with information about this incident, or any other crimes, is urged to report them to 215-686-TIPS. Reports can be made anonymously.
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