Pedestrians walk by a temporary memorial to slain Massachusetts Institute of Technology police Officer Sean Collier in Cambridge, Mass., Friday, Oct. 18, 2013. The granite memorial was unveiled on the... more 
Pedestrians walk by a temporary memorial to slain Massachusetts Institute of Technology police Officer Sean Collier in Cambridge, Mass., Friday, Oct. 18, 2013. The granite memorial was unveiled on the MIT campus Friday morning. Authorities allege the Boston Marathon bombing suspects shot and killed Collier on April 18 to get his gun as they tried to make their escape. (AP Photo/Elise Amendola) less 
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Associated Press | Photo By Elise Amendola
Fri, Oct 18, 2013 2:50 PM EDT