CHICAGO (CBS) — Several out-of-state canine teams are here in Chicago to help with NATO security – teams from the federal Bureau of Alcohol, Tobacco, Firearms and Explosives.

As WBBM Newsradio’s Steve Miller reports, ATF Special Agent Randall Dockens, 43, came to Chicago all the way from Fort Worth, Texas. His co-worker for the past seven years came with him.

LISTEN: WBBM Newsradio’s Steve Miller reports

“This is my canine partner Charlie,” Dockens said. “He’s one of ATF’s explosive detection canines.”

Charlie just turned 9 years old. He’s a black lab – and his claim to fame is his nose.

“He’s capable of detecting approximately 19,000 different explosive combinations,” Dockens said.

Dockens and Charlie got into Chicago – and their first assignment was checking out Wrigley Field. We caught up with them at McCormick Place.

“Our mission is to do whatever the Secret Service or the State Department need us to do, and that basically means employing Charlie’s nose anywhere in the city they think his nose needs to be,” Dockens said.

The ATF won’t say how many canine teams are here – but a spokesman says teams are in Chicago from all over the country.