Charlie Hebdo defied threats and firebombs 'to poke fun at everything in France'
The French satirical magazine where the shooting took place has a history of causing controversy with cartoons of Islam's prophet Mohammed.
Charlie Hebdo is a weekly political and social French newspaper which does not carry adverts and insists its content is not influenced by external shareholders. The name simply means Charlie Weekly - Charlie is thought to be a jokey reference to both the cartoon character Charlie Brown and former French President Charles de Gaulle.
Reports from France have suggested yesterday's attack was carried out during an editorial conference to discuss the next issue of the magazine - an Islam-themed edition.
It was not the first time that the publication had been targeted by extremists, however. The newspaper's offices were firebombed three years ago after it published a special edition entitled 'Charia Hebdo' and "invited" the Prophet Mohammed to be its guest editor. No one was injured in that incident.
Speaking after the attack in November 2011, the editor-in-chief Stephane Charbonnier - who was killed in yesterday's outrage - said the incident had only confirmed that the newspaper was right to take the stance it did.
He said: "This tells me we are right to publish the magazine, and we are right to continue defying Islamists and make their lives difficult as much as they do ours.
"If we can poke fun at everything in France, if we can talk about anything in France apart from Islam or the consequences of Islamism, that is annoying."
Being a target for fanatics is nothing new to the media in Northern Ireland. In September 1976, the Belfast Telegraph was targeted in an IRA bomb that killed one worker and injured many others.
A van was loaded with a bomb and driven into the loading bay of the newspaper's offices on Royal Avenue. It detonated, causing devastating damage - but the editorial team were determined the next edition of the paper would not be stopped.
The staff managed to produce a small newspaper, "which was really an act of defiance", according to former editor Ed Curran.
The paper also had dozens of vans firebombed, and at least one other huge device planted near the paper's offices on another occasion was defused.
In 2007 Charlie Hebdo reprinted 12 controversial cartoons of the Prophet Mohammed that were first published in a Danish newspaper, Jyllands-Posten, and caused outrage in the Muslim world. The magazine was sued for incitement to racism by two Islamic groups in France, but was cleared by a Paris court.
Mr Charbonnier insisted that the publication of Mohammed caricatures was no provocation, but a signal free speech was alive and well in the country. He also said the paper would not stop criticising whatever it wanted.
The issue which is believed to have led to the attack in 2011 featured a cover showing Mohammed saying: "100 lashes if you are not dying of laughter." It also featured an editorial attributed to the prophet and more cartoons, including him with a clown's red nose. Any depiction of Prophet Mohammed is strictly prohibited in Islam.
Established in 1969, the magazine was launched as monthly publication Charlie Mensuel. A year later it became a weekly, but closed in 1982 after running into financial trouble. However, a decade later Charlie Hebdo was back on the shelves printing its satirical material, and in 2009 it celebrated its 900th edition and launched a website.
In 2012 it courted controversy once more by publishing cartoons satirising two films, The Untouchables and Innocence Of Muslims. With the tagline, 'The Intouchables 2', the cover of one issue featured an Orthodox Jewish man pushing a Muslim man in a wheelchair.
My View: Tom Johnston
Charlie Hebdo is a newspaper that has always stood for liberty and attacked oppression, no matter where it came from. These fundamentalist terrorists have murdered four of France's greatest cartoonists because they ridiculed maniacs who want to enforce a perverted interpretation of the Islamic religion. Sadly they have died for their courage. All cartoonists who believe in liberty will be willing to fill the breach. Now, many more cartoons will be aimed at the extremists. They have not stopped the laughter and ridicule, they have turned up the volume.
Belfast-born Tom Johnston was cartoonist for the Daily Mirror, the London Evening Standard and The Sun from 1982 until 2010.
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