On Wednesday afternoon, Kildare gardaí seized a small amount of drugs while on patrol on the Heuston to Waterford rail service - the line also services Athy & Newbridge.
The patrol is part of the Gardaí's on-going operation with Irish Rail, to prevent anti-social behaviour.
Kildare Gardaí confirmed the expansion of the operation, as it has been successful in limiting anti-social behaviour on Dublin's commuter lines accessing Kildare.
One Kildare gardaí noted walk-throughs busy commuter trains are also taking place, mostly on Friday evenings.
Garda districts in the Dublin Metropolitan area are taking part: