The incident happened at about 7 p.m. on Castleton Avenue in the West New Brighton section.
Police found 16-year-old Shane Kelly outside a house. He had been shot in the abdomen.
He was pronounced dead at Richmond University Medical Center, about a block from the scene.
The shooting followed some kind of dispute, investigators said.
No weapon has been recovered, and so far there has been no description of the suspect.
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