A suspicious package containing a powdery substance mailed to Marion County Sheriff Chris Blair was taken out of the sheriff's office early Friday morning.
The powder will be tested by health department professionals in Jacksonville, according to a press release. The incident occurred around 8:50 a.m.
An assistant who opened the letter immediately called for help and emergency protocols were activated. The assistant was not injured.
The letter contained a direct threat to Blair, officials said.
Along with the fire department, Marion County Sheriff's Office bomb squad, major crimes division and the Homeland Security and counter terrorism investigations unit were called to clear the scene.
The FBI and the Florida Department of Law Enforcement will be investigating the incident, in conjunction with the sheriff's office.
"This is serious," Blair said in a statement. "The emotional stress on our employees will not be tolerated. Disrupting MSCO business will not be tolerated. And the emergency resources that were used could have been elsewhere protecting the community."
"We will use all appropriate resources to track down the person or people responsible, he said."