Police and politicians have called for calm amid warnings against misinformation as violence broke out in Dublin following a knife attack on a woman and three young children near a school.

Irish Justice Minister Helen McEntee labelled the scenes in the city centre “intolerable”, and said a “thuggish and manipulative element must not be allowed to use an appalling tragedy to wreak havoc”.

Garda Commissioner Drew Harris said a “complete lunatic faction driven by far-right ideology” is behind disorder in the capital.

Violence broke out after three young children and a woman were attacked Parnell Square East in the north of the city centre on Thursday afternoon.

A five-year-old girl is undergoing emergency treatment for her injuries, Irish police have said.

The Herald: A bus and car on fire on O’Connell Street A bus and car on fire on O’Connell Street (Image: (Brian Lawless/PA))

The woman was seriously injured while the two other children, a five-year-old boy and a six-year-old girl, sustained less serious injuries

Gardai said a man who sustained serious injuries is a person of interest in their investigation.

Earlier on Thursday, Garda Superintendent Liam Geraghty said they 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 appeared minded not to rule that out.

“I have never ruled out any possible motive for this attack… all lines of inquiry are open to determine the motive for this attack,” he said.

“Until we’re sure what the motive is then we have to keep an open mind as to why this happened.”

The scene of the incident is close to Irish language-medium primary school Gaelscoil Cholaiste Mhuire.

A Garda public order unit was deployed in the area around Parnell Square, Parnell Street and O’Connell Street as protesters started to scuffles with officers and flares and fireworks were thrown at the Garda cordon.

As the violence escalated, a bus and car were set on fire on O’Connell Bridge in the heart of the city centre.

The Luas trams service was suspended after coming under attack.

Rioters looted a Foot Locker store on O’Connell Steet as bottles were thrown at gardai on the famous Dublin street.

Other people carried metal bars and smashed shop windows.

In a series of co-ordinated presses, gardai dispersed a large portion of the crowd onto nearby roads.

Smoke from bus and car fires filled the air while a garda helicopter monitored the situation overhead.

Ms McEntee said: “A thuggish and manipulative element must not be allowed to use an appalling tragedy to wreak havoc.

“I have spoken to local TDs from all sides of the Dail and we are of the same view.

“We will not tolerate a small number using an appalling incident to spread division. I would appeal for calm in the city centre as An Garda Siochana carry out their work – attacks on members of An Garda Siochana must be utterly condemned and will be dealt with severely.

“Most importantly, we must remember the real tragedy of today and allow the investigations take their course.”

Speaking to media at Mountjoy Garda Station on Thursday evening, Mr Harris called for calm and spoke out against the spreading of misinformation.

He confirmed that a number of Garda vehicles have been damaged.