The Committee to Protect Journalists condemns Wednesday’s attack on French satirical magazine Charlie Hebdo in Paris.

French media reported that hooded gunmen stormed the magazine’s offices, killing at least 12 people and critically wounding at least five.

Journalists and police officers were believed to be among the casualties. The gunmen fled.

“This is a brazen assault on free expression in the heart of Europe,” said CPJ Deputy Director Robert Mahoney. “The scale of the violence is appalling. Journalists must now stand together to send the message that such murderous attempts to silence us will not stand.”

The magazine was firebombed in 2011 after it ran a spoof edition on Islam.