By ADAM GOLDMAN and MATT APUZZO Associated Press
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Designating an entire mosque as a terrorism enterprise means that anyone who attends prayer services there is a potential subject of an investigation and fair game for surveillance.
Since the 9/11 attacks, the NYPD has opened at least a dozen "terrorism enterprise investigations" into mosques, according to interviews and confidential police documents. The TEI, as it is known, is a police tool intended to help investigate terrorist cells and the like.