Nassau County Police said the incident happened at around 1:40 a.m. in Roslyn, in front of the historic Roslyn National Bank and Trust Company building, located at Old Northern Boulevard and Remsen Avenue.
The 38-year-old victim told police he was walking to his parked car when three men dressed in all black and wearing masks approached him.
One of the men pulled out a knife and shoved the victim to the ground before punching him in the face and removing his jewelry, he told police.
The three men then fled in a white car heading southbound on Old Northern Boulevard.
Police said the victim refused medical attention at the scene.
Anyone with information is asked to contact Nassau County Crime Stoppers at 1-800-244-TIPS. All callers will remain anonymous.
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