A police officer watches an entrance to the Billie Jean King National Tennis Center during the U.S. Open tennis tournament in New York, Wednesday, Sept. 7, 2011. From bomb-sniffing dogs to pat-downs ... more 
A police officer watches an entrance to the Billie Jean King National Tennis Center during the U.S. Open tennis tournament in New York, Wednesday, Sept. 7, 2011. From bomb-sniffing dogs to pat-downs of fans, security will be tight at 13 NFL games and the U.S. Open tennis tournament on Sunday, the 10th anniversary of the 9-11 terrorist attacks.(AP Photo/Charlie Riedel) less 
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Associated Press | Photo By Charlie Riedel
Wed, Sep 7, 2011 3:05 PM EDT