WLS-TV(CHICAGO) — Police and politicians gathered Friday to “honor a life distinguished by service and sacrifice” at the funeral for Chicago police officer Conrad Gary, who was struck and killed by a train in the line of duty Monday.

Gary was an Air Force sergeant who served overseas before spending 18 months at the Chicago Police Department.

He died at age 31 and is survived by his wife and young daughter.

At Friday’s service, Chicago Mayor Rahm Emanuel described Gary as a “brave officer, heroic veteran, loyal friend, the cherished son, the beloved brother, the devoted husband and the proud father.”

The mayor said Gary’s daughter “will grow up in a world that knows her father, respects her father and cherishes the memory of her father as a hero.”

Gary and fellow officer Eduardo Marmolejo were chasing a suspected gunman when they were both hit and killed by a train Monday night. The suspected gunman was later taken into custody.

Gary and Marmolejo climbed a hill to the tracks, looking for the fleeing suspect and evidence, “determined to get yet another illegal weapon off the streets of Chicago,” Chicago Police Superintendent Eddie Johnson said at Friday’s service.

It was “this sense of urgency that led them to put the thoughts of their own well-being aside,” Johnson said. “Their only concern was bringing the offender to justice and getting that gun off the streets.”

Gary’s colleagues expected him to quickly rise up the ranks within the Chicago Police Department, Johnson told mourners.

“Unfortunately Conrad never got that opportunity because he made the ultimate sacrifice for all of us,” he said. “Every citizen of this city should be proud to call officer Conrad Gary one of their own.”

Gary “devoted this life to protecting others,” according to the family GoFundMe page. “He is loved by so many and will truly be missed.”

“Conrad is a true American patriot, a true American hero,” Illinois Gov. Bruce Rauner said. “He’s an Air Force veteran, a Chicago police officer, dedicated public servant, who we will never forget.”

Marmolejo’s funeral is set for Saturday.

Gary and Marmolejo’s deaths are the third and fourth in the line of duty deaths for the Chicago Police Department this year.

In November, Chicago police officer Samuel Jimenez was fatally shot in the neck while trying to protect employees and patients during a shooting at Chicago’s Mercy Hospital.

In February, Chicago police Cmdr. Paul Bauer was shot and killed. Bauer, survived by his wife and daughter, had been sitting in his squad car when he heard a call over the radio and pursued a gunman on foot.

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