Updated 18:30
Irish Rail has said delays are expected on Galway and Westport services for the rest of the day.
The rail operator says significant delays are expected to services as a result.
It comes after a Dublin Heuston to Galway train hit a herd of cows near Tullamore, Co Offaly earlier.
It is understood to have happened shortly after 3pm this afternoon.
Up to eight cows have been badly injured as a result.
The train is still at the scene and has been badly damaged.
Barry Kenny from Iarnrod Eireann says services to and from the West will be disrupted:
“The train is stopped and can’t move at this particular point in time,” he said.
“We are dispatching maintenance personnel to the site.
“We are also dispatching customer service personnel – because what we want to do because the delay is likely to be significant is to get the people on board off the train, if it is safe to do so.
“But it will cause major disruption now with all between Heuston and Athlone, Heuston and Galway and Heuston and Westport – in both directions.”
Update: Significant delays expected to Galway and Westport services for the remainder of the evening due to a herd of cows hit on the line near Tullamore https://t.co/eohFpGysFL
— Iarnród Éireann (@IrishRail) June 28, 2018
Iarnród Éireann has apologised for the inconvenience caused.