The shooting started just before 1 a.m. at 801 North Broad Street, across from the Metropolitan Opera House, authorities said.
A 45-year-old man was hospitalized in critical condition with a gunshot wound to the left eye, while a 42-year-old man was shot in the right thigh and is said to be stable.
Thirty-three pieces of "ballistic evidence" were recovered by detectives at the scene, the department said.
Anyone with information is asked to call 215-686-8477 or submit a tip through the PPD website.
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