The crimes, at least eight so far, have all happened in the Allerton section during the month of November.
In the latest incident on Monday evening, a 15-year-old boy waiting for his train at the subway station at White Plains Road and Allerton Avenue had his headphones snatched off his head. Other victims have had cash and jewelry stolen.
Several other robberies were more violent, including a 31-year-old man who was punched in the face and robbed of $5,000 and others who were jumped from behind and robbed of phones and jewelry.
Police are asking anyone with information to call Crime Stoppers at 1-800-577-TIPS or go to NYPDcrimestoppers.com