This morning, Taoiseach Enda Kenny signed a book of condolence for the victims of the Paris shootings at the French Embassy in Dublin.
On Wednesday, gunmen broke into the offices of Charlie Hebdo, called for some of the staff by name and carried out a shooting.
Tributes have been paid to the staff online with the hashtag #JeSuisCharlie.
Last night, US president Barack Obama last night paid his respects at the French Embassy in Washington.
The Paris terror suspects are holed up at an industrial building near Charles de Gaulle airport and two people have reportedly been killed.
Reports also say that 20 people have been injured and Said and Cherif Kouachi have taken hostages. Police are thought to be negotiating with the suspects.
A conflicting report by Reuters says that one person has been killed, while Paris prosecutors say there are no deaths.
Two planes have aborted landing attempts at the airport as the situation unfolds.
It follows a car chase on the N2 motorway in which gunshots were fired between the men and police as their stolen car headed towards Paris.