NEW YORK, NY - SEPTEMBER 09: A New York City subway enters a station while en route into Manhattan during the morning commute on September 9, 2011 in New York City. Security is being tightened in New ... more 
NEW YORK, NY - SEPTEMBER 09: A New York City subway enters a station while en route into Manhattan during the morning commute on September 9, 2011 in New York City. Security is being tightened in New York and Washington, DC following the detection of a possible terror threat tied to the tenth anniversary of the 9/11 terror attacks. New York City and the nation are preparing for the 10th anniversary of the terrorist attacks on lower Manhattan, which resulted in the deaths of 2,753 people at the World Trade Center. (Photo by Spencer Platt/Getty Images) less 
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Getty Images | Photo By Spencer Platt / Getty Images
Fri, Sep 9, 2011 12:07 PM EDT