CAMBRIDGE — Six months to the day that his life was violently ended, MIT police Officer Sean Collier was honored Friday in a solemn ceremony that marked the crime scene with a memorial stone carved from the university’s Great Dome.
“It’s painful in the extreme to try and remember that six months ago, at this very hour, Sean Collier was still with us,’’ MIT Police Chief John DiFava told about 200 people gathered in a small plaza off Main and Vassar streets.
DiFava recalled Collier, who had achieved a lifelong dream of becoming a police officer, in words that alternated between light-hearted and emotional. For the 27-year-old bachelor, DiFava said, “every day was a good day. It never rained. As long as you had money in your pocket, life was good.”
Collier was shot dead about 10:20 p.m. April 18, allegedly by accused Boston Marathon bombers Tamerlan and Dzhokhar Tsarnaev, as he sat in a marked MIT cruiser parked in the plaza. Three days earlier, according to law enforcement investigators, the brothers detonated homemade bombs near the Marathon finish line that killed three people and injured more than 260.
DiFava fought back tears as he spoke at the 10-minute ceremony, attended by Collier’s sister, Jennifer Lemmerman; L. Rafael Reif, president of the Massachusetts Institute of Technology; university and Cambridge police; MIT employees; and dozens of passersby who stopped to listen during rush hour.
Surveying the large, silent crowd in front of him, DiFava said, “You can’t help but think that this is a testament not to a situation, but to a man.’’
The limestone memorial was fashioned from parts of the Great Dome saved after renovations. The marker features a rendering of an MIT police emblem topped by Collier’s badge number, 179.
Window signs inscribed with “Collier Strong” faced the memorial site, which was adorned with American flags and flowers.
The gathering to honor Collier included Christina Giacobbe, chief administrative officer of the Cambridge Police Department. “He was a good officer, a great human being,’’ Giacobbe said. “He did a lot for this community. He was taken away from us way too prematurely.’’
Employees from many parts of the university began their day with the 7:30 a.m. ceremony. One of them, Tony Missett, wore a shirt that read “Grounds Department Mourns with MIT Police.”
For Missett, a Malden resident who has worked at the university for 32 years, the service was part of a personal healing process. “I consider these police my family,” he said.
There had been no plans for the early morning remembrance until four MIT officers approached DiFava earlier this week with the idea to commemorate the six-month anniversary of Collier’s death. At first, DiFava said, he balked.
“I guess I was in avoidance; I guess I didn’t want to face the fact,” DiFava said in an interview after the ceremony. “It’s still hard to believe that this could happen. This kid was a good kid.”
Shortly after Collier was killed, Tamerlan Tsarnaev died in the early morning hours of April 19, following a shootout with police in Watertown that involved his younger brother.
Dzhokhar Tsarnaev, who was found hiding in a boat in Watertown later that day, is being prosecuted in federal and state courts in Collier’s killing and faces federal charges related to the Marathon bombings.
Brian MacQuarrie can be reached at macquarrie@