Dublin violence: What do we know so far?

More than 30 people were arrested during a riot in Dublin on Thursday, following an earlier knife attack in the city centre which left four injured.

One police officer was also seriously injured in the unrest and many more were hurt.

So what do we know so far?

How did the events unfold?

Gardaí (Irish police) were called shortly after 13:30 local time on Thursday to an incident, in which a woman and three children were hurt in a stabbing near a primary school.

A man in his late 40s, who was also seriously injured, is a person of interest, police said.

While they are not looking for anyone other than a man involved in the incident, investigators are "keeping an open mind" about any motive.

Hours after the stabbing a riot broke out.

Garda Commissioner Drew Harris, who is Ireland's most senior police officer, said there had been an "element of radicalisation" to the riot.

He said gardaí had been "constantly monitoring" social media in the aftermath but the "crowds who were filled with hate were then supplemented by crowds only interested in looting and disorder".

In the unrest that followed, rioters set off flares and fireworks, looted shops and attacked police in Dublin during several hours of disorder.

• Follow live: Dublin violence on level 'not seen for decades'

The "extraordinary outbreak of violence" had come after "hateful assumptions" were made based on material circulating online in the wake of the stabbings, he added.

It is understood that included false claims that the attacker was a foreign national.

Sources have indicated to the BBC that the man suspected of carrying out the attack is an Irish citizen in his late 40s who has lived in the country for 20 years.

The Irish police chief said the force has "not seen a public order situation like this before"

Public transport was disrupted in parts of the Irish capital throughout the night, while the ambulance service said it was "extremely busy".

Many people had to walk home because they could not get a taxi or public transport.

Calm was restored between 20:30 and 21:00, police said.

Who was injured?

A five-year-old girl is in a critical condition following the knife attack. Another six-year-old girl sustained head injuries and a woman in her 30s is seriously ill.

A boy, aged five, has minor wounds and has been discharged from hospital.

In the riot that followed one police officer was seriously injured.

Has there been other damage?

A burned out Luas (tram) is removed from O'Connell Street in Dublin

More than a dozen shops were damaged or looted, while 11 police vehicles, three buses and a tram were destroyed.

A clean-up operation in the city is ongoing and a burned-out tram has been taken away.

Debris is cleared from a burned out Luas and bus

Reflecting on the events, Commissioner Harris told the press what had happened was "extraordinary", adding that such scenes have not been seen "for decades".

The Taioseach (Irish PM) Varadkar said the cost of repairs and clean-up is likely to be in the "tens of millions" of euros.

He adds that there will be government help available for businesses whose premises were damaged by rioters.

Who is behind the violence?

Mr Harris said there was "huge destruction from a riotous mob", which police have blamed on a "lunatic, hooligan faction driven by far-right ideology".

Irish Minister for Justice Helen McEntee said it was not something that "we have seen before" and that a "violent mob of thugs and criminals whose sole focus was to wreak havoc," was responsible.

Social media comments have played a role in the riots according to the Irish government and Gardaí.

There were 34 arrests with 32 before the court on Friday morning.

Twenty-eight men and four women are facing various charges including theft and public order offences.