Cristopher Rosario, 18, of Bloomfield, met the boy in the parking lot of the Walmart on Passaic Street, then threatened him with a silver knife before fleeing on the bicycle towards Passaic shortly after 8:30 p.m. last Thursday, June 1, Capt. Mario Pozo said.
The youngster had gone there after Rosario agreed on Facebook Marketplace to buy the bike for $850, the captain said.
Garfield detectives interviewed the victim, identified Rosario as their suspect, then set up an undercover sting.
Rosario agreed to a transaction with possibly another potential victim in Passaic on Wednesday, June 7, Pozo said.
He was met instead by Garfield Detective Sgt. Marc Amos, Detective Sebastian Tyburski, Detective Erik Dudek and Officer Jonathan Librizzi, who were assisted by their Passaic colleagues, the captain said.
He was arrested before he knew what hit him.
The 5-foot-6-inch, 130-pound Rosario -- who Pozo said was carrying the knife used in the Garfield holdup -- was charged with armed robbery and weapons offenses.
He remained held Thursday in the Bergen County Jail pending a first appearance in Central Judicial Processing Court in Hackensack.
Garfield Police Chief Richard Uram thanked Passaic police for their assistance. He also urged citizens to take any and all steps to avoid becoming a victim during an online sale.
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