The shots rang out on July 7, around 12:57 a.m., on the 1500 block of S. Etting Street.
Three people died and nine others suffered non-life-threatening injuries.
The victims who died have been identified as 24-year-old Azir Harris, 23-year-old Zahir Wylie and 19-year-old Jason Reese.
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On Tuesday, police released photos of suspects they say are wanted in the shooting.
A $20,000 reward is being offered for information that leads to an arrest.
MORE | Video shows multiple people opening fire in Grays Ferry mass shooting that left 3 people dead
Video shows multiple people opening fire in Grays Ferry mass shooting that left 3 people dead