In a moving ceremony, the MIT community paid respects to Officer Sean Collier today. Here is the New York Times coverage of the memorial:

Campus Officer Is Mourned at M.I.T.
By Jess Bidgood
CAMBRIDGE, Mass. — More than 10,000 people, many of them uniformed police or military officers, gathered Wednesday on a tightly secured athletic field at the Massachusetts Institute of Technology to remember Sean A. Collier, the campus police officer who authorities say was gunned down by the suspects in the Boston Marathon bombings.
Officer Collier’s brother, Rob Rogers, looked over the crowd, which included Vice President Joseph R. Biden Jr. and Senator Elizabeth Warren, Democrat of Massachusetts, and took a breath.
“People ask me, if Sean were here, what would he think? Are you kidding me? He would love this,” Mr. Rogers said. “You’ve got sirens, flashing lights, formations, people saluting, bagpipes, taps, the American flag. He would have loved it.”
Officer Collier, 27, was remembered as a curious and charismatic officer who had wanted to be a policeman since he was 7 years old. He took an active role in campus life, said M.I.T.’s president, L. Rafael Reif, asking students about their studies and joining the outdoors club, whose conditioning workouts — climbing 21 flights of stairs — he performed in full uniform.
“In just 15 months, he built a life with us that was rich in friendship and shared adventure,” Dr. Reif said. “And he touched people across our community with his deep kindness and openhearted willingness to help, his humor and enthusiasm, his playful charm.” Read more.