It's because of a signalling fault.
Services between Maynooth and Louisa Bridge are suspended.
Irish Rail says it is because of a signalling fault.
Services are operating from Clonsilla to Connolly station.
Dublin Bus is honouring valid rail tickets between Maynooth/Leixlip and City centre
Due to the signalling fault between Maynooth and Leixlip Louisa bridge. Services are currently operating from Clonsilla to Connolly station. Dublin bus is honouring valid rail tickets between Maynooth/Leixlip and City centre - MH https://t.co/o0n51TZLLy
— Iarnród Éireann (@IrishRail) May 28, 2021

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