ATTENTION EDITORS! This is to clarify the captions of the following images: 124367846 124367923 The pictures were taken in New York City. The caption should read: NEW YORK, NY - SEPTEMBER 09: Amtrak... more 
ATTENTION EDITORS! This is to clarify the captions of the following images: 124367846 124367923 The pictures were taken in New York City. The caption should read: NEW YORK, NY - SEPTEMBER 09: Amtrak Police Sergeant R.A. Smith and K9 Zorro patrol Penn Station September 9, 2011 in New York City. U.S. government officials said yesterday evening that there is a "specific, credible but unconfirmed threat" to the U.S. homeland as the 9/11 anniversary approaches and that New York and Washington were specifically mentioned as possible targets. (Photo by Chip Somodevilla/Getty Images) We apologize for any inconvenience. less 
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Getty Images | Photo By Chip Somodevilla / Getty Images
Fri, Sep 9, 2011 1:59 PM EDT