Gardai were called to East Road in the north inner city at around 9:20pm yesterday. Upon arrival, emergency services found one teenager with serious injuries and one 16-year-old in critical condition.
Later on a third teenager was “presented” with serious injuries.
Gardai reported all three were transferred to Mater Hospital, where the 16-year-old was later pronounced dead.
Local authorities have enforce traffic diversions to keep cars away from the scene.
Gardai crime scene investigators are carrying out examinations of the incident.
A source close to the incident told Dublin Live the first two victims were in “very bad condition”.
One line of inquiry being investigated by the Gardai is whether the teen were involved in a dispute with another young man.
Investigators believe the youths were involved in an incident with a delivery driver prior to the “fatal assault”.
A full statement from the Gardai said: “Gardaí are currently investigating all the circumstances of a fatal assault and associated incidents which occurred this evening on East Road, East Wall, Dublin 3, 26th January 2021.
“At approximately 09:20pm Gardaí received report of a public order incident occurring on East Road, East Wall.
“Gardaí and emergency services attended the scene and two juvenile males were taken to the Mater Hospital to be treated for serious injuries.
“One of the juvenile males has subsequently been pronounced dead in the Mater Hospital. A third male has since presented to the Mater Hospital to be treated for injuries.
“Gardaí are appealing for anyone who was in the East Road, East Wall area between 9:00pm and 9:40pm and may have any information or footage (including dash cam), to contact Store Street Garda Station on 01 666 8000, the Garda Confidential Phone Number 1800 666 111 or any Garda Station.”