They followed one buyer out of the area, then watched another meet with Jonathan Delgado, 25, on Jersey Street before moving in on Monday, city Public Safety Director Jerry Speziale said.
The investigators arrested the buyer and Delgado, who lives several blocks away on Market Street.
He had 62 bags of cocaine, along with a .380 Feg Army handgun and $303 in proceeds, in his car, Speziale said.
Delgado was charged with drug and weapons offenses and sent to the Passaic County Jail to await a first appearance in Central Judicial Processing Court in Paterson.
Detectives also charged the buyers -- both men, one 59 from Garfield and the other 46 from Paterson -- and released them pending local court hearings.
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