Arizona prison officials are investigating whether faulty locks may have allowed an inmate to open his cell door and attack a nurse last week.
And just to be sure such an attack doesn't happen again, every cell door at the Arizona State Prison in Phoenix has been newly equipped with a second locking device, officials said recently.
Warden Melvin Thomas said officials now believe that inmates may have been able to force cell doors open by kicking them from the inside or jiggling them enough to dislodge the locking mechanism.
But Thomas disputed allegations that officials had known for years that the 80-year-old locks were faulty, saying that he first heard of problems on Sept. 29.
'There have been incident reports talking about specific doors, and those were taken care of immediately,' Thomas said. 'As far as a systemic problem, I'm not aware of that.'
Springs in the locking mechanisms that hold cell doors shut wear out over time and have been outfitted through the years with new springs. In October, Thomas said the prison ordered new locks, but they have not arrived.
The nurse had exited the medical records room in the King's Ward of the Flamenco Unit - which houses mentally ill inmates - when she was assaulted from behind and knocked unconscious, said Camilla Strongin, spokeswoman for the Arizona Department of Corrections.
The nurse was found about 3 a.m. in the inmates' shower room with injuries to her head and back. It remained unknown whether she was sexually assaulted.
One inmate has been identified as a suspect in the attack, but his name has not released.
All 26 inmates on the ward were locked in their cells when the nurse was found.