He's being treated for serious injuries after an alleged assault on O’Connell Street in Dublin yesterday
Gardaí said the 18-year-old was assaulted after leaving a premises on the street between 3:30 pm and 4 pm yesterday afternoon.
He was taken to the Mater Hospital where his injuries are described as serious.
Investigators said the suspect fled the scene.
An 18-year-old man was arrested a short time later by Gardaí from Store Street.
He was released in the early hours of this morning and the Garda investigation is ongoing.
Gardaí are appealing to anyone who was in the area at the time and may have witnessed the assault to contact them.