Sean Collier sworn in as Somerville police officer

Posted: 08/22/13 at 10:55 pm EDT      Last Updated: 08/22/13 at 11:34 pm EDT

SOMERVILLE, Mass. (WHDH) -- The tears were as plentiful as the pride inside Somerville City Hall Thursday night.

“He was my best friend. You know? He was my brother, I really…sorry…I…he should be here,” said Collier’s best friend, Brandon Kelly.

Sean Collier was officially made a Somerville police officer, given badge number 310.

Just weeks before he was officially going to be made a Somerville police officer in May, police said the Tsarnaev brothers killed Collier while he was working as an MIT officer. But Somerville has always been his dream and the city presented his family with his badge, and then retired the badge number.

“No one will ever hold Somerville 310 again. That will forever be Sean’s,” said Collier’s brother, Andrew.

Collier’s friend and police academy buddy, Officer Dick Donohue, said it was a touching gesture. Donohue was also hurt during the shoot out following the Marathon bombings.

“It’s a dream he always wanted to do and not all of us can do our dreams and achieve those. He loved being a police officer, he loved the city of Somerville,” said Donohue.

Collier’s family said they always knew he’d be an officer and this honor is helping to mend their hearts.

“It is filling but I don’t know if we’ll ever be full,” said one family member.

They hope the spirit of Collier’s strength and compassion will also help heal the community he so loved.

“Remember to be strong, be Collier strong. Do it for MIT officer 179 and Somerville officer 301,” said Andrew Collier.

Collier’s brother said he’s been called many things: a hero, a brother, a great friend. But he would have been most proud to be called a great cop.

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