On Wednesday, the Paris offices of Charlie Hebdo, the French satirical magazine, were attacked by gunmen, who killed 12 people and wounded nearly a dozen others.

According to a number of reports, the three attackers, bearing Kalashnikovs and a rocket launcher, entered the building shouting "Allahu akbar!" and started firing shortly after noon local time. The men escaped by car and later exchanged gunfire with police; there is currently a major manhunt underway in Paris.

French President Francois Hollande characterized the attack as being both “of exceptional barbarity” and "a terrorist attack without doubt." He added, "We are threatened because we are a country of liberty."

In the 45-year history of Charlie Hebdo (minus an 11-year absence from 1981-1992), the magazine, like many satirical outfits, has run all kinds of material that has invited controversy and provoked ire, much of it simply irreverent, some of it political and stridently anti-religious.

Most notably, in 2006, the magazine republished the infamous cartoons of Mohammed that ran in the Danish newspaper Jyllands-Posten as well as another caricature of the Islamic prophet in 2011. After the latter episode, the magazine's offices were firebombed.

(Michel Euler/AP)

Stéphane "Charb" Charbonnier, the magazine's editor who was said to have been killed in the attack along with a number of well-known French cartoonists, appeared on "al-Qaeda's Most Wanted" list in 2013.

A New Yorker profile of Charlie Hebdo in 2012 featured this quote, which Charb delivered to the French newspaper Le Monde about his magazine's controversies and the corresponding threats of violence.  

I don’t feel as though I’m killing someone with a pen. I’m not putting lives at risk. When activists need a pretext to justify their violence, they always find it.

While many details are still unclear about Wednesday's attack, the magazine issued this tweet shortly before the shooting: a cartoon featuring Islamic State leader Abu Bakr al-Baghdadi saying in French, "To your health." The tweet itself translates as, "Best wishes, by the way."

According to The Telegraph, this week's issue of the magazine features a story about a new novel by Michel Houellebecq, which is also being released in France today. "The book is about a Muslim running France according to the laws of conservative Islam," the newspaper wrote.

Condemnations of the attack have started to stream in from governments around the world.

In an early statement, the White House used the "strongest possible terms" to condemn the attack. President Obama later added, "France is America’s oldest ally, and has stood shoulder to shoulder with the United States in the fight against terrorists who threaten our shared security and the world. Time and again, the French people have stood up for the universal values that generations of our people have defended."

British Prime Minister David Cameron tweeted: "The murders in Paris are sickening. We stand with the French people in the fight against terror and defending the freedom of the press."

German Chancellor Angela Merkel also added that the "shooting in France is not only an attack on French citizens, but on freedoms of press and speech."

Wednesday's shooting is the deadliest attack in France in at least two decades. With Hollande set to address the country on Wednesday evening, France has raised its security alert to its highest level.