Detectives Mohammad Bashir and Yamil Pimienta, responding to a report of a group assaulting two victims, approached a group of of four on the corner of Jefferson and North 5th Street, city Public Safety Director Jerry Speziale said.
As they got out of their car, the detectives saw one hand a plastic bag to another and tell him to run.
The boy, 17, tossed the bag as he ran through rear yards on North 4th Street before Detectives Mustafa Dombayci and Suquan Gary nabbed him on North 3rd Street, Speziale said.
They recovered 170 heroin folds stamped "Get High" and "Fireball" and eight baggies of pot, along with what Speziale described as a 9mm Taurus semi-automatic handgun and a high-capacity magazine.
The boy was sent to the Essex County Juvenile Detention Center in Newark. The gun was sent to State Police to determine whether it may have been discharged in crimes.
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