At around 10 a.m. Wednesday, May 11, the man walked into the M&T Bank on East Putnam Avenue in Cos Cob and demanded cash, Greenwich Police said.
He was given an undisclosed amount of money before fleeing the scene.
The suspect is described as a man standing 5-feet-10-inches tall, weighing approximately 175 pounds. Surveillance footage showed him wearing a dark hoodie, sunglasses, and a face mask.
He also had on dark pants, possibly with paint on them.
Anyone with information is asked to contact the Greenwich Police Department at 203-622-8004 or the confidential tip line at 203-622-3333.
Tips can also be emailed to tips@GreenwichCT.org.
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