One inmate was stabbed and two others were injured when two separate fights broke out at the maximum security federal prison Thursday night.
Both incidents, which were not related, spurred a lockdown that remained in effect on Friday.
Each fight involved two inmates who used homemade weapons, according to Scott Pennington, spokesman for U.S. Penitentiary Tucson.
Pennington did not know what the inmates used to make the weapons.
Three of the four inmates were taken to local hospitals for treatment, Pennington said. Two have since been released while the one who was stabbed remained hospitalized in stable condition.
No staff members were injured.
The prison will remain on lockdown pending the investigation. The names of the inmates were not released.
As water lifeline evaporates, Arizona faces a cultural change over water use
