SPECIAL REPORT: The battle for our jails
There are at least 18 major organised criminal gangs operating within the Irish prison system, vying to control an illegal world of drugs, mobile phones and contraband.
It’s a shadow culture that mirrors the brutal world they know from life on the outside, ruled by fear, violence and the hierarchy of the streets.
It has its own systems and currencies – and its own brutal methods of enforcing the rules.
Although Irish gangs are firmly in control, there is also a significant presence of foreign mobs, including Chinese triads and East European Mafia groups.
Official sources put the number of organised crime gangs within the system at around nine, but the Prison Officers Association say that various groupings brings the number up to 40.