During the first incident on November 30, Suffolk County police say 19-year-old Ronnie Langhorn arranged to sell a cell phone to someone in Mastic Beach.
He showed the victim a cell phone and accepted cash before telling the victim he had to get a SIM card, according to police, but he instead fled to the rear of the property and never returned with the phone.
In a separate incident on December 8, Langhorn and three men allegedly arranged for the purchase of a cell phone on Mastic Road, also through the letgo app, and stole money from the victim before fleeing on foot.
In a third incident at the Mastic-Shirley LIRR station on December 31, police say the victim gave Langhorn money before Langhorn pushed him to the ground.
When the victim attempted to follow the suspect, a second man, 21-year-old Mitchell Washington, threatened to shoot him, authorities said.
Langhorn, 19, of Mastic, was charged with robbery, grand larceny and petit larceny. Washington is charged with robbery.
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