The full scale of “an extraordinary outbreak of violence” in Dublin centre has been revealed by police on Friday.
Thirty-four people were arrested after 11 police vehicles, three double-decker buses, trams and other cars were damaged.
Disorder broke out on Thursday night after a woman and three young children were injured in a knife attack near a school.
Garda Commissioner Drew Harris described “an extraordinary outbreak of violence” at a press conference on Friday morning.
He said the scenes – which he described as “huge destruction by a riotous mob” – had not been seen in Ireland “in decades” and blamed people being “radicalised by social media”.
Mr Harris went on to say it was “disgraceful” that the force’s inquiries into the stabbings were interrupted by having to deal with the disorder.
“We can’t allow the city to be given over to the thugs and to the looters and to the arsonists,” he added.
There were clashes with riot police as some demonstrators let off flares and fireworks, while others grabbed chairs and stools outside bars and restaurants.
Mr Harris said 13 shops had been significantly damaged or looted.
A police cordon was set up around the Irish parliament building, Leinster House, and officers from the Garda Mounted Support Unit were in nearby Grafton Street.
Roads around O’Connell Street were blocked by public order gardaí as bins were set on fire in parts of city.
Irish Justice Minister Helen McEntee labelled the scenes “intolerable” and said a “thuggish and manipulative element must not be allowed to use an appalling tragedy to wreak havoc”.
Mr Harris said a “complete lunatic faction driven by far-right ideology” was behind the disorder.
Earlier on Thursday, Garda Superintendent Liam Geraghty said officers were keeping an open mind in terms of the investigation but were “satisfied there is no terrorist link”.
However, at an evening press conference Mr Harris was asked about a potential terrorist link, and said: “I have never ruled out any possible motive for this attack... all lines of inquiry are open to determine the motive for this attack.
“Until we’re sure what the motive is then we have to keep an open mind as to why this happened.”
A Garda public order unit was deployed in the area where a police vehicle was set alight.
Some threw bottles and fireworks at gardaí while others carried metal bars and smashed shop windows.
Many of those attacking officers had hoods up and their faces covered.
Tram services in Dublin city centre were suspended amid the violence while rioters looted a Foot Locker store on O’Connell Steet.
In a series of co-ordinated presses, gardaí dispersed a large portion of the crowd onto nearby roads.
Smoke from fires filled the air, while a Garda helicopter monitored the situation overhead.
Ms McEntee said: “We have a complete lunatic hooligan faction driven by far-right ideology, and also then this disruptive tendency engaged in serious violence.
“We are drafting in resources to deal with that and that will be dealt with properly. I’ve given full direction to our resources here in respect of making arrests and bringing offenders to justice.
“It’s our responsibility to make sure that we police the streets, and part of that is we ask people to act responsibly and not to listen to the misinformation and rumour that is circulating on social media.
“The facts are being established, but the facts are still not clear on a lot of the rumour and the innuendo is being spread for malevolent purposes.”
Speaking about the stabbings, Mr Geraghty said passers-by had intervened during the attack before a man in his 50s was detained. The Garda are not looking for anyone else in connection with the incident.
He said: “An Garda Siochana continue to investigate all of the circumstances of a serious assault which occurred on Parnell Square East shortly after 1.30pm this afternoon.
“Preliminary indications are that a male attacked a number of people on Parnell Square East.
“Five casualties have been taken to hospitals in the Dublin region.
“These casualties include three young children, an adult female and an adult male.
“One girl, aged five years, has sustained serious injuries and is currently receiving emergency medical treatment in CHI Temple Street.”
The scene of the incident was close to Irish language-medium primary school Gaelscoil Cholaiste Mhuire.
Witnesses reported seeing victims with what appeared to be stab wounds.
Onlooker Siobhan Kearney said she saw a man attacking children during the incident. She described what she saw as “absolutely bedlam”.
Ms Kearney told national broadcaster RTE she watched people disarm a man who she said had a knife.
“I looked across the road and I see the man and the stabbing motion with a load of children so I flew across the road.
“The man was after stabbing two children, as far as I could make out,” she told the broadcaster.
“People were trying to attack the man so me and an American lady, we formed a ring around the man, and then about three minutes later the ambulance came for the children and then another ambulance and fire officers came for the man on the ground.”
Mr Harris confirmed that bystanders intervened.
“It would appear that following the actual incident itself, and as part of the incident itself, members of the public who were passing by intervened and in effect then grappled with this individual and that allowed gardaí on arrival to arrest that individual,” he said.
Dublin city councillor Nial Ring said he had spoken to a woman who “on seeing the attack confronted the attacker with another man – I understand he was a Deliveroo cyclist – and managed to get the knife off him.
“Those two citizens are real heroes and probably prevented even more carnage.”
Photos and videos on social media showed a huge emergency response at the scene.
A spokesperson for the Garda described it as “a serious public order incident" and confirmed other emergency services were assisting at the scene on Parnell Square East, which remained sealed off.
Taoiseach Leo Varadkar said: “We are all shocked by the incident which has taken place in Parnell Square.
“A number of people have been injured, some of them children. Our thoughts and our prayers go out to them and their families.
“I have been in contact with the Minister for Justice who is keeping me updated. The facts in this matter are still emerging.
“The emergency services responded very quickly and were on site within minutes. I thank them for that.
“Gardaí have detained a suspect and are following a definite line of inquiry.”
Social Democrats TD Gary Gannon said: “An attack on children is an act of absolute cowardice and depravity.”
Irish Justice Minister Helen McEntee said she was “deeply shocked” by the “appalling attack on three innocent children".
Ms McEntee said: “All our thoughts are with those injured, especially with the children, their parents and families, during this extremely difficult period.
“This attack has shocked us all, and I have no doubt that the person responsible will be brought to justice."
Sinn Fein leader Mary Lou McDonald said the incident in Dublin city centre had caused “shock and horror”.
In a social media post, Mrs McDonald said: “Violent attack at Gael Cholaiste Mhuire Parnell Square has sent shock and horror throughout the community.
“My heart goes out to all the hurt and injured, the parents, teachers but especially the children who have been so traumatised. This is beyond words.”
