Acting Essex County Prosecutor Carolyn Murray says the gunfire erupted in front of a bodega on South 14th Street in Newark around 9:30 p.m.
Laniay Griffin was killed, while a 15-year girl and a 16-year-old boy were wounded. Their names have not been released, but the boy's mother identified him as Jamar Robinson.
Police say it appears two suspects walked up to the victims while they sat on a stoop in front of the store and opened fire at close range.
Griffin was shot twice and collapsed near the scene.
The motive is unknown, and no arrests have been made.
Police are hoping a nearby surveillance camera caught the crime on tape.
There is a $5,000 reward being offered by the Essex County Sheriff's Crimestoppers Program.
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