A suspicious substance at the Internal Revenue Service building near Union Station tested negative just before noon Wednesday.
Kansas City Fire Department crews had responded about 10:30 a.m. to the facility at 333 W. Pershing Road to investigate a suspicious package containing a white substance found in an envelope in a room where 70 people had been working.
The “white powdery substance” had been discovered in a letter that carried an “articulated threat,” Bridget Patton, a FBI spokeswoman, said Wednesday. Following protocol, the materials were to be packaged and forwarded to the Missouri Department of Public Health laboratory in Jefferson City for further analysis.
Representatives of the Kansas City Fire Department Hazmat team, as well as the Federal Bureau of Investigation, IRS, U.S. Postal Inspection Service and the Department of Homeland Security Federal Protective Service responded to the scene.