A post mortem will be carried out on his body this afternoon.
A teenage boy has been arrested in connection with last night's fatal stabbing in west Dublin.
The victim of this stabbing, Aaron Keating, was well known and liked in Ongar.
He suffered serious stab wounds at around 7 last night when a row broke out on Main Street.
People in the area at the time rushed to try and help him but he was pronounced dead in Connolly Hospital.
A post mortem will be carried out on his body this afternoon.
Aaron Keating was in his 40s and known to state services for personal issues.
Earlier this morning, Gardaí arrested a teenage boy on suspicion of murder.
He has been brought to a garda station in the west of the city for questioning.
An incident room has been set up at Blanchardstown Garda Staton and anyone with information is being asked to come forward.

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