Charlie Hebdo is a left-wing satirical newspaper published every Wednesday, known for its cartoons and comic strips, which often feature controversial religious stories.
Among the most notorious cartoons are the paper's depictions of the Muslim prophet Muhammad. Some Muslims believe it is an offence to make a visual depiction of the prophet, and the newspaper does not tread lightly, often using particularly crude imagery. Its coverage has frequently been criticised and its offices were targeted in 2011 in what was thought to be a retaliatory attack.
In September 2012, it published a series of cartoons of the Muhammad, some of which included nude caricatures. It was shortly after the anti-Islamic 'Innocence of Muslims' film was released on YouTube and the newspaper's decision drew criticism from the French government.
The foreign minister, Laurent Fabius, said: "In France, there is a principle of freedom of expression, which should not be undermined. In the present context, given this absurd video that has been aired, strong emotions have been awakened in many Muslim countries. Is it really sensible or intelligent to pour oil on the fire?