It happened just after 1 a.m. Sunday, October 3 inside the Albany houses on Troy Avenue in Crown Heights.
A ShotSpotter Siren was also activated.
Video shows the gunman approach 22-year-old Roshad Twells before pulling out a gun and opening fire.
Twells was found dead in front of the building.
It's not clear what led up to the deadly violence.
Anyone with information in regard to the identity of this individual 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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