Armed with rifles and other weapons, they killed 12 people and injured 11 others.
The gunmen identified themselves as belonging to the Islamic terrorist group which took responsibility for the attack.
Several related attacks followed in the Île-de-France region on 7–9 January 2015, including the Hypercacher kosher supermarket siege where a terrorist held 19 hostages, of whom he murdered 4 Jews.
France raised its Vigipirate terror alert and deployed soldiers in ÃŽle-de-France and Picardy.
A major manhunt led to the discovery of the suspects, who exchanged fire with police.
The brothers took hostages at a signage company in Dammartin-en-Goële on 9 January and were shot dead when they emerged from the building firing.
On 11 January, about two million people, including more than 40 world leaders, met in Paris for a rally of national unity, and 3.7 million people joined demonstrations across France.
The phrase Je suis Charlie became a common slogan of support at the rallies and in social media.
The staff of Charlie Hebdo continued with the publication, and the following issue print ran 7.95 million copies in six languages, compared to its typical print run of 60,000 in only French.