The brazen murder was captured on surveillance video that is too graphic to show in its entirety, but police are hoping it leads to an arrest.
It happened just after 9:30 p.m. Wednesday on Franklin Avenue in the Prospect Heights area.
Arriving officers found 42-year-old Delia Johnson lying unconscious and unresponsive with gunshot wounds to her head and leg.
She was rushed to Interfaith Hospital, where she was pronounced dead.
The video shows the suspect, described as being in her mid-20s with a heavy build and long blond hair, first exiting a white vehicle.
She then walks up behind Johnson, shoots her in the back of the head, and returns to the car, which flees the scene.
No arrests have been made, and the investigation is ongoing.
Anyone with information in regard to the whereabouts 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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