Charlie Hebdo attack: the response in pictures
There has been an outpouring of posts on social media in the wake of the attacks in Paris, with 1.3m tweets alone using the hashtag #CharlieHebdo.
This graphic (in English: "I am Charlie") was shared more than 140,000 times in the first hours after the attacks.
The magazine itself then published a PDF with the same phrase translated into seven different languages.
Le Monde and L'Express cartoonist @plantu tweeted this image. The text reads: "We are wholeheartedly with Charlie Hebdo".
A 2012 cartoon from the New Yorker was shared more than 6,000 times in the first few hours after the attack.
Charlie Hebdo's editor-in-chief Gerard Biard, who was in London during the attack, said: "I don't understand how people can attack a newspaper with heavy weapons. A newspaper is not a weapon of war." Cartoonists picked up on the 'mighty pen' theme.
There were many variations on the theme questioning how lethal a cartoonist can actually be. The cartoon below says: "Why? ... Pump-action rifle? ... Kalashnikov? ... Grenade?"
Previous Charlie Hebdo covers were also being shared on social media. The text of the most popular reads: "Love is stronger than hate" and shows the editor of the magazine kissing a figure that many have interpreted as the Prophet or one of his followers.
That front cover was published after the magazine's offices were attacked in Nov 2011.
Dutch cartoonist Ruben Oppenheimer drew parallels between Wednesday's shootings and the 9/11 attacks.
Australian cartoonist David Pope shared an emotional tweet that was shared more than 30,000 times.
Some posters went straight to the heart of the issue by sharing a cartoon by the French artist Delize. The text reads: "Believers hurt by non-believers" (the man crying on the left) and "Non-believers hurt by believers." (the man lying in the pool of blood on the right).
Blog by Sitala Peek
You can follow BBC Trending on Twitter @BBCtrending
All our stories are at bbc.com/trending