A Revere, Mass. police captain holds his cap while entering a memorial service for fallen Massachusetts Institute of Technology police officer Sean Collier, in Cambridge, Mass., Wednesday, April 24, ... more 
A Revere, Mass. police captain holds his cap while entering a memorial service for fallen Massachusetts Institute of Technology police officer Sean Collier, in Cambridge, Mass., Wednesday, April 24, 2013. Collier was fatally shot on the MIT campus Thursday, April 18, 2013. Authorities allege that the Boston Marathon bombing suspects were responsible. (AP Photo/Steven Senne) less 
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Associated Press | Photo By Steven Senne
Wed, Apr 24, 2013 2:10 PM EDT