The incident, which is believed to involved a knife, took place in the Stoneybatter area of Dublin 7.
A man was arrested near the scene a short time after the incident.
Gardai have stressed there is no risk to the wider public at this time.
All three people injured in the incident have been taken to hospital but there are injuries are not believed to life-threatening.
The incident that unfolded in the Stoneybatter area of Dublin on Sunday afternoon is not believed to be terror related, according to sources.
It is believed that three people injured in the attack were all Irish and all were attacked randomly.
The attacker is believed to be from South America.
It is believed that some of the people injured had their faces slashed.
All of the people who sustained injuries have been taken to hospital where their injuries are not believed to life-threatening at this time.
Gardai issue statement
A gardai spokesperson said: “We are currently at the scene of an incident in the Stoneybatter area of Dublin 7.
“A male has been arrested and is currently detained at a Garda station in the North City.
“There is no ongoing risk to the public at this time.
“Further information will be provided when available.”
Gardai and other emergency services are at the scene of a reported stabbing in Dublin.
It is believed at least three people were injured by the one attacker in the Stoneybatter area of Dublin.
A suspect has been apprehended, according to reports on social media.
