Police say the two men were standing outside the Soundview Houses Sunday night when a gunman walked up to them and opened fire.
Stephon Brown, 19, was shot in the back and killed.
His 21-year-old brother was struck in the arm and is in stable condition at the hospital.
There are no arrests at this point, and it's not clear what led to the shooting.
The investigation is ongoing, and anyone with additional is asked to call the NYPD's Crime Stoppers Hotline at 1-800-577-TIPS (8477) or for Spanish, 1-888-57-PISTA (74782).
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