Police officers march in formation as they enter St. Patrick's Church, in Stoneham, Mass., before a funeral Mass for Massachusetts Institute of Technology police officer Sean Collier Tuesday, April ... more 
Police officers march in formation as they enter St. Patrick's Church, in Stoneham, Mass., before a funeral Mass for Massachusetts Institute of Technology police officer Sean Collier Tuesday, April 23, 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
Tue, Apr 23, 2013 2:51 PM EDT