Two workers at a federal detention center in the state capital are dead and another injured after Tuesday morning's shooting.
The FBI says a guard opened fire when investigators came to arrest six corrections officers.
FBI spokesman John Girgenti says the gunfire was exchanged with the guard as he tried to leave the building. He won't say whether the shooter is among the dead or injured, but police earlier said the shooter was in custody.
Tallahassee police say the three victims were initially taken to a hospital, but Girgenti later said two died. The condition of the third is not yet known.
Meanwhile, Federal Bureau of Prisons spokeswoman Carla Wilson says the institution is in lockdown status.