Three people were hospitalised in the incident in which a Garda car and taxi were struck.
A crazed driver was seen erratically driving his BMW near St Stephen's Green before he smashed through traffic on the busy South Quays - writes dublinlive.ie
The rampage saw the 20-year-old strike a garda car after heading toward the Quays where he sped up Wellington Quay and Aston Quay.
The man, originally from an Arab background, then struck a taxi and a truck before coming to rest.
Gardai were swiftly on the scene and began treating those injured.
A search of the car found a large number of items including a copy of the Koran.
Three people were hospitalised following the incident, which happened just after 2pm.
A source said: “There are reports this man was seen driving his BMW erratically in the Stephen’s Green area of the city.
“He was said to be in what appeared to be a distressed state and he then made his way down to the quays.
“Initially he was treated by the Garda Armed Support Unit who were rapidly on the scene and then he was taken out of the car by fire service.”
As the area was being forensically examined a number of detectives appeared at the scene.
They are understood to be from the National Bureau of Criminal Investigation, who investigate serious crime and terrorist activity, and removed at least four evidence bags of items from the car.
A source added: “At the moment theories are that this man was in a very disturbed state and was having an episode.
“He is receiving treatment now in hospital.
“The presence of the NBCI was part of the broader investigation.
“It is certainly a major incident to have a car driving like this in any city and there is a significant concern from a security perspective regarding car and truck attacks.
“There is nothing immediately evidentially to say this has anything to do with terrorism but it must be examined.”
A Garda press office spokesman said yesterday: “Gardai in Pearse Street are investigating a serious four-car collision on Wellington Quay.
“One of the cars involved was an official garda car. Three people have been taken to hospital.
“The road remains closed. We have no further information at this stage.”
The Garda Siochana Ombudsman Commission said they had not been requested to investigate the incident.
Wellington, Aston and Burgh Quays was closed to traffic for five hours as emergency services dealt with the incident, with delays continuing for several hours after it was re-opened to traffic.
As a result of the massive delays bringing Dublin’s city centre to a standstill, College Green was temporarily re-opened for outbound traffic.
Despite drivers and pedestrians being told to avoid the area, crowds could be seen gathering on the pathways surrounding the road where thecrash took place.
Heavy knock-on delays were reported around the area, as well as busy routes such as Pearse Street, Dame Street, Leeson Street and Merrion Square.
There were also diversions in place for some of the busiest routes for Dublin Bus and Bus Eireann.
Just before Christmas Dublin City Council installed armoured barriers disguised as flower pots across popular shopping areas in a bid to stop a terror attack like those in London, Barcelona and Nice.
The planters act as blockades for heavy vehicles and were placed at the various entrances of Grafton Street and Henry Street in consultation withAn Garda Siochana.
While they look harmless with small trees in them, the planters are actually made of ultra strong reinforced steel designed specifically to stop cars and lorries from entering the busy tourist and shopping zones.
Similar barriers can be found across Europe’s major cities.
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