LONDON — Ireland's prime minister on Friday condemned anti-immigrant protesters who rampaged through central Dublin after three young children were stabbed, saying the rioters simply wanted to cause chaos, not protect the country's way of life.

Police made a number of further arrests on Friday evening as they mounted a significant security operation in Dublin to ensure that there was no repeat of Thursday's disorder. A number of people were taken away in police vans following sporadic altercations.

Police arrested 34 people after Thursday night's rioting when up to 500 people looted shops, set fire to vehicles and threw rocks at crowd control officers equipped with helmets and shields.

The violence began after rumors circulated that a foreign national was responsible for the attack outside a Dublin school on Thursday afternoon. Authorities haven't disclosed the suspect's nationality.

Prime Minister Leo Varadkar said Ireland's capital had endured two attacks, one on innocent children and the other on "our society and the rule of law."

"These criminals did not do what they did because they love Ireland, they did not do what they did because they wanted to protect Irish people, they did not do it out of any sense of patriotism, however warped," Varadkar told reporters on Friday morning. "They did so because they're filled with hate, they love violence, they love chaos and they love causing pain to others."

A 5-year-old girl was in critical condition at a Dublin hospital and a teacher's aide was in serious condition, police said. A 6-year-old girl continues to receive treatment for less serious injuries and another child was discharged overnight. The alleged assailant, who was tackled by witnesses, remains hospitalized in serious condition.

Thursday's unrest came amid rising tensions over immigration in Ireland that mirror trends in other parts of Europe. Earlier this year, people carrying signs reading "Ireland is full" demonstrated in Dublin, and protesters blockaded a hotel housing asylum-seekers in County Clare on the west coast.

An analysis of more than 13 million social media posts over the past three years found that right-wing groups were increasingly using platforms such as X, formerly known as Twitter, to stir up opposition to immigration. Recent activity has characterized the refugees and asylum-seekers as an "existential threat to Ireland," according to a report from the Institute for Strategic Dialogue, a London-based group that seeks to combat extremism.

Ireland received more than 141,000 immigrants in the 12 months through April, the highest total since 2007, the latest government statistics show. The influx of migrants drove an 11.7% increase in Ireland's population over the past 11 years, contributing to a steady increase in housing prices.

When he was questioned about anti-immigration tensions earlier this year, Varadkar told Ireland's parliament that there was always a place for peaceful protest, but violence, intimidation and racism were never legitimate.

"I think when it comes to this matter, we should never lose sight of the bigger picture — we're facing a major refugee crisis not just here in Ireland but all across Europe," he said in May.

Commissioner Drew Harris, head of Ireland's national police force, described those who took part in Thursday's unrest as a "complete lunatic hooligan faction driven by far-right ideology."

More than 400 officers, including many in riot gear, were deployed throughout the city center to contain the violence. A cordon was set up around the Irish Parliament building, Leinster House, and mounted officers were dispatched to nearby Grafton Street.

One officer was seriously injured in clashes with the rioters, some of whom were armed with metal bars and covered their faces.

"These (riots) are scenes that we have not seen in decades, but what is clear is that people have been radicalized through social media and the internet,'' Harris told reporters.

"But I don't want to lose focus on the terrible event in terms of the dreadful assault on schoolchildren and their teacher. There's a full investigation ongoing. There's also a full investigation in respect on the disorder."

Varadkar praised people of multiple nationalities who intervened to stop the attack as it unfolded, describing them as "real Irish heroes.''

One of them was Caio Benicio, a Brazilian delivery driver who stopped when he saw the teacher's aide trying to save the children. Spotting a knife, he ripped off his helmet and slammed it into the attacker with all his strength.

"I pray for her to survive,'' Benicio said of the child in critical condition. "I'm a parent myself, I have two kids and I know how hard it is."

Benicio told Britain's Press Association that the disturbances seemed to be caused by a "small group of people" who "wanted an excuse to do what they did.''

"I'm here for about 20 years now, I don't know politics here deeply to have an opinion about it," he said. "What I can say is I know the protest is against immigrants and for me it doesn't make sense, because I'm an immigrant myself and I was the one who helped out. For me it doesn't make sense."

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