The Arizona Department of Corrections says the death of an inmate at the Tucson prison complex is being investigated as a suspected homicide involving an assault.
The department says investigators believe 30-year-old Richard Noriega's death Tuesday resulted from injuries suffered when he was assaulted by another inmate.
Noriega died at a Tucson hospital where he was taken after prison staff found him breathing but unresponsive on Monday.
Noriega was serving a 13-year sentence on Pima County Superior Court convictions for aggravated assault, forgery, unlawful use of transportation and armed robbery.
