Police are offering a $30,000 reward for information leading to the arrest and conviction of the person pictured above.
Quran Garner, 18, and Rashaan Vereen, 34, were arrested and charged earlier this week in connection with Saturday's shooting on South Street, CBS3 reports.
Gregory Jackson, 34, Alexis Quinn, 27, and 22-year-old Kris Minners all were pronounced dead at hospitals, according to police and those who knew the victims.
Investigators told the news outlet that a fight between three men ignited the chaos.
A police officer shot and wounded Garner, who was apparently seen firing into a large crowd on the southwest corner of South and American Streets, according to the outlet.
Police say the pictured suspect should be considered armed and dangerous.
Anyone with information is urged to call the Philadelphia police at 215 686-TIPS(8477) or the PPD Homicide Unit at 215-686-3334.
Click here for more from CBS3.
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