An investigation is being carried out after a fire broke out on a Dublin-bound train outside Newry, Co Down.
There were 114 passengers on board the 6.05pm Belfast to Dublin Enterprise train when the fire broke out in the engine compartment.
The driver pulled up at Gorawood, a disused station north of Newry.
Carriages were moved away from the train while the fire was brought under control by the Northern Ireland Fire Service.
There were no injuries.
Group commander Eddie Carroll said fire crews had difficulty getting into the engine area.
"The initial crews, on arrival, were confronted with a well-developed fire," he said.
Irish Rail brought passengers to Dublin's Connolly Station on a replacement train.
Passengers eventually arrived in Dublin almost five hours later than scheduled.
Northern Ireland Transport Minister Danny Kennedy said there would be a full investigation to establish the cause of the fire.
Speaking to RTÉ'S Morning Ireland, Irish Rail Communications Manager Barry Kenny said the company was sorry for the inconvenience caused to passengers.
"The fire service in Northern Ireland obviously was called to the scene. Ultimately, the train couldn't be moved at that time and there was a very significant delay," said Mr Kenny.
Mr Kenny rejected suggestions that Irish Rail and Translink, the Northern Irish rail provider that jointly runs the Belfast line with Irish Rail, should have provided passengers with bus transfers instead of waiting over four hours for a replacement train to arrive.
Mr Kenny also confirmed that Irish Rail provided hotel accommodation to three passengers and private taxis to 20 others to help them complete their journey once they arrived in Connolly Station.