Groups of teenagers clashed at a seaside beauty spot and at a Dublin Dart station leaving at least one young person in hospital.
Rival groups reportedly engaged in a running battle down the pier of the seaside town of Howth this afternoon at about 4pm.
Missiles and bricks were reportedly thrown as they went, and at least three people were treated for injuries at the scene, with at least one of those transported to hospital with a head injury.
"There were a gang of 60 plus teenagers out for trouble," a source told Dublin Live.
"They walked to top of the pier, causing havoc in the area."
Gardai responded quickly and maintained a presence in the area after the majority of the youths were cleared.
But the clashes in the city continued as youths fought at a north Dublin Dart station mere moments later.
At least 20 teens were seen getting into fights on and around trams at Kilbarrack station.
Services were suspended by Iarnroid Eireann after reports of trespassing on the tracks at around 5:30pm.
Irish Rail tweeted that Gardai were called to the scene to clear the mess.
Services through the station resumed after around 45 minutes.
Dublin Live have contacted An Garda Siochana for comment on both incidents.
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