No weapon was shown, and no one was hurt, said Norwalk police Lt. Terry Blake.
In an image from the bank's surveillance system that was posted on the Norwalk Police Department's Facebook page, the robber is seen entering the bank wearing the mask, dressed in a black coat and black gloves. A second photo shows the suspect at the counter pointing with a gloved index finger.
Matthew Nuzzo, who works at Letizia Pizza across the street from the bank, said everything was quiet until the police arrived.
He said he saw a police vehicle pulled up to the bank and joked with two customers, "'What the heck, did the bank get robbed?' I thought it was a traffic stop, I was making a joke and then more cops showed up," Nuzzo said.
He said there was nothing suspicious before the robbery, and he never noticed a vehicle speeding away from the scene.
Detectives remained on the scene conducting an investigation.
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