Trains travelling to and from Dublin to the south of Ireland on Wednesday morning have been delayed for up to an hour.
Cork, Kerry and Limerick trains are affected in both directions due to a mechanical fault with an on-track machine.
Irish Rail said the machine had been cleared from one line and that services were back moving but delays would continue. A crane is being brought on site to remove the machine, and was set to arrive at 10am.
Passengers have reported seeing a digger on the track to Dublin near Templemore in Tipperary.
Irish Rail said the 6.15am train from Cork to Heuston was no longer non-stop due to disruptions and would stop at a number of stations enroute.
The Portlaoise commuter service was also subject to delays.
