World leaders, journalists and members of the public have all condemned the attack on Charlie Hebdo offices, which left 12 people dead.
Al Jazeera round some of the comments made over the past 24 hours.
Dalil Boubakeeur, President of Muslim Council in France
"Truly, Islam condemns assassination, condemns murder, condemns taking the lives of those around you. Truly. And we are absolutely horrified, we are stunned."
John Kerry, US Secretary of State
"The pen is an instrument of freedom, not fear."
Christophe DeLoire, Reporters without Borders
"This is the darkest day of the history of the French press."
David Cameron, British Prime Minister
"We stand squarely for free speech and democracy. These people will never be able to take us off those values."
Matteo Renzi, Italian Prime Minister
"I think all of Europe is crying today. All the free world is crying. All men and women who believe in freedom and reason are crying."
Cecile Electon, Arts worker
"This is bad for everyone - particularly for Muslims despite the fact that Islam is a fine religion. It risks making a bad situation worse."
Patrick Hertgen, Emergency Services medic
"What we saw was a massacre."
Unnamed official source, Saudi Arabia
"The Kingdom of Saudi Arabia has followed with deep sorrow the terrorist attack" at the Charlie Hebdo magazine,SPA said, citing an unnamed official source.
It said the source condemned "this cowardly terrorist attack which is incompatible with Islam".
Marzieh Afkham, Iran's Foreign Ministry Spokeswoman
"Such behaviors are the continuation of the wave of extremism as well as physical and intellectual violence that has been spreading unprecedentedly across the world throughout the past decade..."
Yusuf al-Qaradawi, Islamic Scholar
We, the Muslim scholars, strongly condemn any action that sheds innocent blood and claims the lives of innocent people, spreading corruption on earth, whoever the perpetrators are and whatever their religion.