Boston bombing victims: Photo shows slain, injured Mass. officers together

WILMINGTON, Mass. A vigil has been held in Massachusetts for an MIT police officer authorities say was shot and killed by the alleged Boston Marathon bombers.

Hundreds turned out Saturday night in Wilmington to honor 26-year-old Sean Collier, who grew up in the town about 15 miles north of Boston.

Authorities say Collier was shot in his cruiser Thursday night on the MIT campus in Cambridge. He lived in Somerville and was preparing to become a police officer in that city.

The Boston transit agency on Sunday released a photo of Collier with Richard Donohue, the 33-year-old transit police officer who remains hospitalized after authorities said was seriously wounded in a gun battle with the bombing suspects.

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The photo was from a 2010 graduation ceremony at the Municipal Police Officers' Academy.

Collier's former boss, Somerville Deputy Police Chief Paul Upton, told CBS News correspondent Terrell Brown that it's not how Collier died that made him a hero but how he lived.

"Sean lived to be a good police officer," Upton said. "That was his goal in life, that's what he wanted to be, that's what he was."