Article Photos: As Boston buries its dead, more evidence gathered 20/26

Mourners walk past police motorcycles as they depart St. Patrick's Church in Stoneham, Mass., following 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. A truck that belonged to Collier sits behind. (AP Photo/Steven Senne)