A Brazilian delivery driver branded a hero for helping subdue a knife-wielding assailant suspected of attacking children outside an Irish school told AFP Saturday that he acted "like every parent would".

A five-year-old girl sustained serious injuries and remains in hospital following the stabbing attack, which then sparked the worst night of rioting in Ireland's capital Dublin for nearly two decades.

Authorities say that unconfirmed reports circulating on social media that the stabbings were carried out by an "illegal immigrant" ultimately sparked the disorder, which saw vehicles burned and stores looted.

Caio Benicio, who works for the Deliveroo takeaway app, used his motorcycle helmet to stop the unnamed suspect as he allegedly stabbed three children and a woman.

The 43-year-old and other interventions by passers-by were praised by Irish prime minister Leo Varadkar, who branded them "the real Irish heroes".

But Benicio -- a dad to a 12-year-old boy and daughter, 19 -- said that he does not think of himself as "a hero", as he revisited the scene of the horrific attack in Dublin. 

"I'm a parent. I have two kids myself. I think every parent would do the same," he said of his spur-of-the-moment actions. 

"It's something that you don't think about, (you) just act."

Benicio was greeted by numerous people on the street, who shook his hand and commended him for his bravery.

He said the local response and a call from his children were "priceless".

"It's nice to make them proud," he told AFP. "That's very, very nice."

The Brazilian was aided in disarming the attacker by a trainee chef from France, who has been in Dublin on an internship at a local restaurant since October. 

The 17-year-old student, who suffered minor injuries to his hand and face, received a congratulatory phone call from French President Emmanuel Macron on Friday.

Benicio reiterated Saturday that the riot by around 500 people, who authorities have said were encouraged by far-right agitators, "makes no sense".

"The protest is against immigrants, and I'm an immigrant myself and I was the one to help out," he added.

"Anyway, I think it was a small group of people (responsible) that they don't even know what they're doing, fighting for."

The Brazilian noted Irish people had always treated him "very well" and were "very friendly" during his time in the country.

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