Mark Zuckerberg has condemned the deadly attack on French satirical magazine Charlie Hebdo and pledged to defend freedom of speech on Facebook.
"I won't let that happen on Facebook. I'm committed to building a service where you can speak freely without fear of violence."
With Zuckerberg's post, Facebook became the latest tech giant to support Charlie Hebdo after the attack.
Google has pledged 250,000 euros ($300,000) to support the publication. A picture of black ribbon appeared on the homepage of the search engine.
The website of the French branch of Apple also featured a message of support for the magazine.
Extremists have used the threat of violence to try to silence Facebook before.
A lawyer in Pakistan fought to have Zuckerberg sentenced to death in 2010, after Facebook hosted a "Draw Muhammad" contest on its site.
Facebook was blocked in Pakistan over the issue, but the ban was lifted a few days later after the company took down the offending page in the country.
Zuckerberg said Facebook follows national laws -- even if that means sometimes removing material at the request of governments -- but will never let "one country or group of people dictate what people can share across the world."
Zuckerberg signed off with #JeSuisCharlie, the hashtag that has become the international rallying cry for people to express their solidarity.