Officials were dispatched to the federal courthouse in Pikeville Monday afternoon after reports of a white powder found inside.

Nine people were decontaminated outside the courthouse before being taken to Pikeville Medical Center. So far, there are no serious injuries being reported.

The FBI is investigating, but officials are not releasing much information.

The U.S. Marshals Office has confirmed other letters were sent to the London and Frankfort Federal Courthouses.

Also, at least four congressional offices in Kentucky received threatening letters that purported to contain anthrax.

The offices of U.S. Reps. Geoff Davis, Brett Guthrie, Ed Whitfield and John Yarmuth received the letters in the mail Monday morning.

Guthrie spokesman Nate Hodson said a staffer in the Bowling Green office opened one of the letters and immediately called authorities. Hodson said the first line of that letter said the envelope contained anthrax.

Davis spokeswoman Alexandra Haynes said a similar letter arrived at the Fort Mitchell office. She said the letter apparently was sent by a prison inmate. She didn't know which prison.

Yarmuth spokesman Trey Pollard said the letter to the Louisville congressman was given to the FBI.

Hodson and Haynes said investigators determined that the anthrax threat was a hoax.

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