An inmate died and another four injured on Saturday after a riot broke out in Gujranwala Central Jail, a private TV reported.
The deceased was beaten to death by an iron rod. His killer was previously accused of beheading his mother.
In May, an Indian spy Sarabjit Singh succumbed to his injuries after two inmates beat him up in Kot Lakhpat Jail, Lahore.
Another prisoner Chamel Singh had died in a jail in April and rumours ran riot that he was tortured. The Punjab Prisons Department claimed that the rumours were part of a malicious propaganda and that the prisoner had died after suffering from a stroke.