NEW YORK (CBSNewYork) – The FBI wants your help finding a suspected bank robber.

Sam Chatman allegedly robbed two Chase Bank branches on the Upper West Side of Manhattan. He allegedly struck the branch at 2438 Broadway at 90th Street on June 18. On July 27, the FBI says he struck again at 2824 Broadway at 109th street.

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Chatman, 54, is described as 5’7″-5’9″, weighs 200 pounds, and is African-American. The FBI says he owns several weapons and should be considered armed and dangerous.

Chatman also likes to gamble: he’s been known to go to casinos.

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“Chatman’s behavior is not only increasingly violent, but completely erratic,” Supervisory Special Agent Barbara Daly said.

The FBI is promising a “significant” reward for the tip that breaks the case. Anyone with any information about Chatman is urged to call the FBI at 212-384-1000. The FBI says people who offer information can remain anonymous.

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Do you know Chatman? Are you concerned about being robbed at your bank? Sound off in our comments section.