One of the men pulled a gun and shot the victim, who then staggered across Olney Avenue and collapsed in front of La Salle University. The victim was not a La Salle student.
He was taken to Albert Einstein Medical Center, where he was pronounced dead about 4:30 p.m., Small said.
Several men were seen fleeing the scene, with the shooter heading north on 20th Street toward Chew Avenue.
The victim was "well-known to police," Small said, and was not affiliated with the school. There's no word on what sparked the argument.
Several witnesses were being interviewed by Homicide Unit detectives.
The shooting occurred feet from where the school's president, Brother Michael McGinniss, lives, according to a source in the university.
The school, which recently celebrated its 150th anniversary, wasn't locked down in the wake of the shooting, and evening classes were still held as scheduled, according to that source.
Anna Melnyk Allen, the school's associate dean of students, declined to comment, referring questions to statements posted on the school's website.
In a statement released just after the shooting, the university's Office of Campus Safety and Security had asked students to remain inside their homes until further notice.
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