Armed gunmen burst into an editorial meeting at the French satiric weekly Charlie Hebdo and murdered twelve people, including journalists and police officers.
The newspaper, often provocative and controversial, had a reputation for publishing cartoons that lampooned all sectors of society, but especially religion and politics.
In 2005, it drew worldwide attention for publishing caricatures of the prophet Muhammad.
The gunmen, who reportedly shouted "Allahu Ackbar" and "the Prophet is avenged" may have been retaliating against the paper for this reason.
Political cartoonists across Europe gave statements in response.
Salman Rushdie expressed his solidarity with those who died.
Vigils were held worldwide.
The gunmen fled and have not yet been found.