The Lord Mayor of Dublin has described the attack as "evil and devastating".
It's understood that at least three children have been stabbed in Dublin City Centre.
An Garda Síochána are currently at the scene of a serious incident on Parnell Square East and are being assisted other emergency services.
Five (5) casualties have been taken to various hospitals in the Dublin Region.
The casualties include an adult male, an adult female and three young children.
One child, a girl, has sustained serious injuries, the other two children are being treated for less serious injuries. An Garda Síochána is in contact with parents of all three injured children.
An Garda Síochána is following a definite line of inquiry and are not looking for any other person at this time.
Minister for Justice Helen McEntee said she is "deeply shocked by the appalling attack".
"All our thoughts are with those injured, especially with the children, their parents and families, during this extremely difficult period. I have been briefed by the Garda Commissioner and will remain in close contact with him and senior Gardaí," she said.
The Lord Mayor of Dublin has described the attack as "evil and devastating".
Daithi de Roiste says his thoughts are with the families involved, and he is praying that the victims make a full recovery.
Garda Commissioner Drew Harris says it appears as though members of the public intervened in this incident in Dublin.
He was due to meet with the Policing Authority in Waterford, but was interrupted by the news from the capital.

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