By Jim Williams

CHICAGO (CBS)–New details are emerging about heroic 2nd District Chicago Police Officer Samuel Jimenez, who lost his life Monday after running into the line of fire inside Mercy Hospital.

Mourning for Jimenez, 28, the married father of three children, began Monday night in a police procession and continued Tuesday, as police in the Northwest Side neighborhood where he lived with his family kept watch over his home and prepared ribbons to tie around trees and light poles in honor of the fallen officer.

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Chicago Mayor Rahm Emanuel and Chicago Police Superintendent Eddie Johnson said they knew Officer Sam Jimenez was heroic. Today, they learned more about who Jimenez was as a man.

Samuel Jimenez was killed Monday by a gunman at Mercy Hospital.

“He’s a great husband, great dad, great police officer–but just a great person,” Johnson said.

Those thoughts were echoed at Moretti’s Restaurant in Edison Park, where the young man staff and patrons called “Sammy” served food and bussed tables before he became a police officer.

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Collegaues say Jimenez was always hardworking and protective.

“He was a good kid–he was hardworking,” said Moretti’s manager Karen Kissane. “He was determined to make something of himself.”

Jimenez’s good friend Daniel Torres said his classmates at Northeastern Illinois University were overjoyed when Jimenez found out he got the job as a Chicago police officer.

“It was the happiest moment for all us, for his family, his friends,” Torres said. “He was like, ‘I did it–I’m here. Now it’s time for me to work.'”

Kissane said Jimenez “just wanted to help people” and he “wanted to make things better.”

Melissa McIntyre of the Edison Park Chamber of Commerce said the loss of Jimenez hit the community hard.

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“When this happens, it can be any one of us in this neighborhood,” McIntyre said. “And we just wanted to come out and show our support–not just to remember–but to show his family everyone in the City of Chicago, especially Edison Park, is thinking of them.”