Gardai are investigating an alleged assault on a train in Dublin last night. A teenager is being treated for non life threatening injuries in hospital after he received a stab wound to the chest.
The incident happened on a northbound service between Killester and Harmonstown.
A teenager was arrested shortly after 10pm at Killester Dart Station.
It appears that the victim and suspected offender were known to one another.
Services were suspended for a time between Clontarf and Howth Junction but are now back up and running.