Iarnród Éireann and the Department of Social Protection say they have uncovered widespread fraud in the use of free travel passes issued by the Department in an ongoing inspection blitz launched last weekend.
"Many holders were found to be travelling on out of date passes including one woman who was travelling on a pass that was out of date since 2007", a joint statement said.
"Many others were found to be travelling on a pass that was issued to somebody else", it added.
Passes being used fraudulently were confiscated with fines of up to €100.
Over 50 inspectors were involved in the 7 December blitz checking passes on Cork Commuter lines and services between Athlone-Galway, Mullingar-Dublin and Limerick Junction-Ennis.
Exit checks were also carried out at Connolly, Pearse, Tara Street, and Heuston stations in Dublin.
Iarnród Éireann says more blitzes are planned.
The company says it has allocated extra resources to tackle fare evasion and fraudulent use of free travel passes.