Investigators are on the scene, police said at about 11:15 p.m.
No one was injured, police said via Twitter @NorwalkCtPD.
The bank robbery suspect was described as a black man in his 50s, wearing glasses and using a cane, police said.
He fled in a black sedan, possibly with New York plates, police said.
The Webster Bank is located at 402 Connecticut Ave., near the ShopRite and across from Stop & Shop.
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