It happened on Saturday, July 11 just before midnight in Roslyn.
The victim, now identified as 17-year-old Jarol Hernandez, of Hempstead, was on the ground when officers arrived in the vicinity of Northern Boulevard and Museum Drive, according to Nassau County Police detectives.
Hernandez had suffered from multiple gunshot wounds and was pronounced dead by a Nassau County Police Medic at the scene.
The investigation is ongoing.
Detectives request anyone with information contact Nassau County Crime Stoppers at 1-800-244-TIPS.
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