The incident happened just before noon on October 20 in the Tremont section of the Bronx.
The 74-year-old victim was walking in front of 485 East 180th Street when the suspect approached him and forcibly removed his chain before knocking him to the ground.
The suspect then fled the scene. The victim refused medical aid.
The suspect is described as an 18- to 25-year-old man, approximately 5-foot-8 and weighing 180 pounds. He was last seen wearing a blue hooded sweater, blue sweat pants and black and white sneakers.
Anyone with information in regards to this robbery is asked to call the NYPD's Crime Stoppers Hotline at 800-577-TIPS.
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