Officers, their guns drawn, went through the building floor by floor, but the suspect first was confronted by FBI agents in the lobby of the agency's 12th floor offices, where Hibbard and his alleged victim went via elevator. Hibbard, the knife still in his possession, was taken into custody without further incident, and the hostage was unharmed.
"We don't have a clear indication why he picked that building or why he then went to the FBI offices," Josephson said. "There's no indication he knew the victim, or that he had a particular beef with the government."
Hibbard did make statements to police generally connected to the incident, but "none of them was clear as to why he [allegedly] did this. . . . Why he made the determination to do this is part of our ongoing investigation," Josephson said.
He declined to further detail Hibbard's statements other than to say they seemed coherent, "not bizarre or rambling."
FBI spokeswoman Deborah Bertram on Tuesday declined to discuss what possible connection, if any, Hibbard had to the FBI or what his grievance may have been. However, Josephson said the hostage was not believed to have been an FBI employee.
Hibbard, listed as a Nevada native, was booked into Salt Lake County jail on suspicion of first-degree felony aggravated kidnapping. He was being held without bail pending court proceedings.
The Utah Department of Corrections confirmed Tuesday that Hibbard had been discharged in May 2010 from supervised probation for previous sexual battery and attempted theft by receiving stolen property convictions. Corrections spokesman Stephen Gehrke said Hibbard was being supervised in Utah as part of a probation monitoring agreement with another, unspecified state.
A search of Utah court records shows Hibbard has a criminal record beginning in 1991 that includes misdemeanor convictions for possession of a controlled substance, retail theft, simple assault and forcible sexual abuse.