An unidentified protester rips down the NATO sign on the Chicago River bridge at Michigan Ave., during a demonstration Friday, May 18 2012, ahead of this weekends' NATO summit in Chicago. (AP ... more 
An unidentified protester rips down the NATO sign on the Chicago River bridge at Michigan Ave., during a demonstration Friday, May 18 2012, ahead of this weekends' NATO summit in Chicago. (AP Photo/Charles Rex Arbogast) less 
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Associated Press | Photo By Charles Rex Arbogast
Sat, May 19, 2012 8:58 AM EDT