The investigation began on Monday after 28- year-old inmate Steven Gonzales approached uniformed security officers at the unit to say he was having issues with his cell mate, officials said in a news release.
Gonzales further indicated that officers should go to the assigned cell.
A responding officer approached the cell and found the cell mate lying on the bottom bunk covered with a mattress. He was unresponsive, the release said.
The victim was identified as 30-year-old Bobby Paris. He was serving a six-year sentence after being convicted of sexual assault of a child and forgery.
He had been received by the TDCJ’s Institutional Division on May 19, 2009, from Henderson County.
Security and medical personnel initiated life-saving measures, and the victim was rushed to the infirmary on a gurney.
Emergency medical personnel arrived at the scene and pronounced the offender dead at 5:58 p.m.
TDCJ spokesman Jason Clark said Gonzales has been placed in administrative segregation.
Gonzales was received by the TDCJ on Jan. 15, 2008, from Dallas County to serve a life sentence for murder.