Two Mountjoy prisoners have been taken to hospital following a stabbing incident.
It is reported in various media that Thomas Fox, who is accused of murdering Gareth Hutch last year, was stabbed in a row with another prisoner in the A division of the prison.
Another prisoner, who came to Thomas's aid, was also injured in the fight.
The pair are now being treated at the Mater Hospital.
One is said to have suffered head injuries while the other is thought to have been stabbed in the abdomen.
These injuries are believed to be serious, but not life threatening.
Gardaí are investigating the incident and looking into the possibllity that the attack was feud-related.
Inmates from the Kinahan and Hutch criminal gangs have been separated into different prisons.