CHICAGO (CBS) — One Chicago Police officer doesn’t need an anniversary as a remembrance of 9-11.

As WBBM Newsradio’s Dave Berner reports, Officer Nick Spencer has his personal reminder every day at the end of a leash.

Spencer uses a 3-year-old black Labrador to sniff packages, garbage cans and even commuters at ‘L’ stops.

LISTEN: WBBM Newsradio’s Dave Berner reports

The bomb-sniffing dog is Ggillis, after New York police Sgt. Rodney Gillis, who died when the south tower of the World Trade Center collapsed minutes after he ran inside.

Ggillis is one of many K-9 units named after police officers, firefighters and others killed on 9/11.

“All these people were victimized by terrorist attacks and these dogs, that’s exactly what they fight against,” said Spencer, 45. “These dogs are on our front lines against terrorism.”

Defending those lines took on a greater sense of urgency after terrorists hijacked jets and slammed them into the World Trade Center and the Pentagon. Authorities realized they needed bomb-sniffing dogs at all sorts of transportation centers. After toying with the idea of giving them funny names or ones tied to mythology, the Transportation Safety Administration settled on names that would ensure nobody would forget the dogs’ purpose, said Scott Thomas, manager of the TSA’s Canine Breeding and Development Center.

“The best thing about naming the dogs after 9/11 victims is it keeps us on task,” he said, adding that some dogs have been named after military personnel killed in Afghanistan and Iraq. The program adds an extra first letter to each dog’s name to identify it as a participant.

Last year, Spencer was with training Ggillis outside Wrigley Field, where a New York officer was attending a Cubs game.

“He heard me say her name and said, `That’s a weird name for a dog,”‘ Spencer said. “When I told him, `She’s named after one of your guys,’ he gets choked up.”

The officer knew Rodney Gillis.

In all, more than 530 police officers work with bomb-sniffing dogs named for fallen first responders on Sept. 11. Officers say the dogs provide an opportunity to talk about at least one person who died that day.

“I tell people my dog’s named after someone pretty interesting,” said Josh Diaz, a Chicago police officer who works with Ppearsall, a yellow lab named after New York firefighter Durrell Pearsall Jr. “I tell them, `Do me a favor, look this guy up, Google him.”‘

Gillis’ family said they were honored when they learned there was a dog patrolling Chicago with a black and yellow checkered collar signifying the rank of sergeant.

“All of the heroes we lost, they should be remembered and to be remembered in such a significant way is wonderful,” said Gillis’ mother, Geraldine.

His widow, Serina Gillis, agreed. And, she said her husband “would get a kick out of it. He loved dogs.”

(TM and © Copyright 2011 CBS Radio Inc. and its relevant subsidiaries. CBS Radio and EYE Logo TM and Copyright 2011 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten or redistributed. The Associated Press contributed to this report.)

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