One recent example: Quazi Mohammad Rezwanul Ahsan Nafis, who "thought he was blowing up the Federal Reserve Bank" of New York as part of an FBI sting operation, the commissioner says.

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Last year, the FBI ran that type of test on Quazi Mohammad Rezwanul Ahsan Nafis, a college student from Bangladesh who fell under scrutiny after he began using social media to seek support for a terror attack.

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Bangledeshi national Quazi Mohammed Rezwanul Ahsan Nafis, 21, was arrested after he assembled what he believed to be an operable bomb weighing over 1, 000 pounds in the back of a van, with the intention of attacking the NY Fed.

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