More than 130 gardaí, many heavily armed, commenced raids on houses in the McCarthy-Dundon gang stronghold of Ballinacurra Weston at 7am. Those arrested are in their 20s, 30s and 40s.
When gardaí entered a number of houses they had to break down metal doors which had been erected on stairways.
All those arrested are being held under section 50 of the Criminal Justice Act 2007, which allows gardaí to question them for up to seven days.
Among those arrested are criminals involved in money laundering for the McCarthy-Dundon gang.
A Garda spokesman said: “A lot of work was done in the lead-up to yesterday’s operation involving surveillance. This is the arrest phase, in the utilisation of the new [anti-gang] legislation brought in last year.”
That legislation was introduced following the murder of Limerick businessman Roy Collins.
In yesterday’s operation, divisional Garda search teams were backed up by specialist support units which included the Emergency Response Unit, National Bureau of Criminal Investigation, Regional Armed Support Unit, Special Detective Unit and detectives from the city’s crime units.
A high-profile member of the McCarthy-Dundon gang, recently released from jail, was not among those arrested yesterday. However, a close relative was detained.
Another man arrested had some months ago featured in newspapers over a claim he was brokering a truce with the rival Keane-Collopy gang.