DEVELOPING: Authorities are evacuating the IRS building in downtown Kansas City after a bomb-sniffing dog hit on a vehicle parked outside.

Police spokesman Darin Snapp says the bomb and arson unit was sent, along with agents from the Bureau of Alcohol, Tobacco, Firearms and Explosives.

FBI spokeswoman Bridget Patton said the agency's bomb squad also is at the scene, with authorities "trying to figure out what's going on."

Patton said something suspicious turned up during a routine check of the building's parking garage.

The ATF did not immediately return calls seeking comment.

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