A man in his 60s is in a critical condition in hospital following a suspected hit and run in Ballymun yesterday.
A teenage boy has since been arrested.
Gardai were called to the scene of a collision involving a car and a pedestrian on the Ballymun Road shortly after 3pm yesterday.
The pedestrian, a man in his 60s, was taken to the Mater Hospital where his condition is described as critical.
Officers say the car didn't stay at the scene.
A teenage boy has since been arrested and is being questioned at a garda station in north Dublin, where he can be held for up to 24 hours.
The road was closed for a forensic investigation, and has since reopened.
Gardai are appealing for any witnesses to contact them.
A garda spokesperson says: "Gardaí at Ballymun are appeling for witnesses following a serious injury collision in Ballymun on Thursday 6th July 2023.
"Shortly after 3pm, Gardaí and Emergency Services were alerted following a collision involving a car and a pedestrian on the R108 Ballymun Road.
"The pedestrian, a man aged in his 60s, was removed from the scene to the Mater Hospital where his condition is understood to be critical.
"The car involved failed to remain at the scene.
"A male aged in his late teens has since been arrested and is currently detained under section 4 of the Criminal Justice Act, 1984 at a Garda Station in north Dublin.
"The scene was examined by Garda Forensic Collision Investigators and the road has since fully reopened to traffic.
"Gardaí are appealing for witnesses to come forward. They are also appealing to road users with camera footage (including dashcam) from the area at the time of the collision to make it available to them.
"Anyone with information is asked to contact Ballymun Garda Station 01 666 4400 or the Garda Confidential Line 1800 666 111.
"The investigation is ongoing and further updates will follow."