A New York City police officer examines a commercial vehicle at a checkpoint on 59th St. and Park Ave. on Friday, Sept. 9, 2011 in New York. The city is deploying additional resources and taking other... more 
A New York City police officer examines a commercial vehicle at a checkpoint on 59th St. and Park Ave. on Friday, Sept. 9, 2011 in New York. The city is deploying additional resources and taking other security steps in response to a potential terror threat before the 10th anniversary of the Sept. 11 attacks. U.S. counterterrorism officials are chasing a credible but unconfirmed al-Qaida threat to use a car bomb on bridges or tunnels in New York or Washington. (AP Photo/Jin Lee) less 
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Associated Press | Photo By Jin Lee
Fri, Sep 9, 2011 12:43 PM EDT