The prisoner had been serving a 25-year sentence in a terrorism case when he tried to slit the warden's throat.
In entering a guilty plea Tuesday, Fazliddin Kurbanov admitted using a prison-made knife to attack the warden at the Federal Correctional Institution at Victorville on May 31, 2016.
At the time of the attack, the then-warden — identified only as C.J. — was standing in the dining facility near the serving line. Kurbanov, armed with an approximately 4-inch homemade shank, approached C.J. from behind, wrapped one arm around his neck and tried to slit the warden's throat, according to a plea agreement.
When the warden raised his hand to protect his throat, Kurbanov slashed the left side of his body from armpit to hip bone. C.J. needed about 80 staples to close the wound, "resulting in a permanent disfiguring scar and sharp pains most likely caused by nerve damage."
In a subsequent interview, in which the prisoner had been read his rights, Kurbanov admitted that he made the shank a week earlier and that he had tried to cut the main artery in C.J.'s neck.
The warden, who is now working at another facility operated by the U.S. Bureau of Prisons, was seriously injured but has since recovered.
The investigation into the attack was conducted by the FBI and the case is being prosecuted by the National Security Division of the U.S. attorney's office.
Kurbanov is scheduled for sentencing June 4. As a result of his pleading guilty to one count of attempted murder of a federal officer, Kurbanov faces a sentence of at least 15 years in federal prison to be served consecutively with the 25-year sentence imposed in 2016 by a federal judge in Idaho.
Kurbanov was sentenced in that case for conspiring and attempting to provide material support to the Islamic Movement of Uzbekistan and for procuring bomb-making materials to execute a terrorist attack on American soil, according to then Assistant Atty. Gen. for National Security John P. Carlin.
Between the summer of 2012 and Kurbanov's arrest in May 2013, he was living in Boise, Idaho, and communicating by email and Skype with a person or persons operating a website for the Islamic Movement of Uzbekistan, officials said.
Kurbanov talked about his animosity toward Americans, particularly the military; his desire to build a bomb; possible targets in the U.S.; and his need for instruction on how to construct and remotely detonate a bomb.
Between at least Nov. 15, 2012, and May 16, 2013, Kurbanov possessed bomb-making components at his Boise apartment, including a hollow hand grenade, a hobby fuse, ammunition containing smokeless powder, tannerite, aluminum powder, potassium nitrate, charcoal, yellow sulfur powder and fertilizer.
FBI special agents observed the bomb-making components during a court-authorized search of Kurbanov's apartment in November 2012 and seized many of the same items during a second court-authorized search in May 2013.
Kurbanov's activities were closely monitored by federal agents during the investigation, and no terrorist attack occurred.