Hollywood voiced solidarity with French satirical magazine Charlie Hebdo, as some linked Wednesday's deadly attack on it to the recent freedom-of-speech controversy over a comedy film about North Korea.
Celebrities expressed outrage and support online, while the Motion Picture Association of America made a direct link between the Paris massacre that killed 12 and the hacking and threats to Hollywood studio Sony Pictures over the movie The Interview.
"We are shocked and saddened by the horrific terrorist attack at Charlie Hebdo that occurred today," said MPAA head Chris Dodd in a statement.
"Our industry has experienced firsthand cowardly attempts (to destroy) freedom of speech, and we offer our expression of support to the victims and their families, as well as the French people."
Sony Pictures initially resisted demands by hackers that it cancel the film's December 25 release date. But it gave in the week before Christmas, before changing its mind again and releasing it from December 24.
The Screen Actors Guild (SAG) called the Paris attack -- in which masked gunmen shouted "Allahu akbar" -- a "despicable act of terrorism."
"Journalists know that their jobs carry risks, but these brazen killings were particularly shocking in that these journalists were not operating in an overseas combat zone, but were at work in their own offices in a democratic nation," it said.
Hollywood stars took to Twitter and other social media to voice solidarity with the French publication, and France more generally.
"Obviously this is terrible and tragic and upsetting," said comic actor Tina Fey, cited by industry journal Variety.
"It makes you remember how important free speech is and must be defended. We all must stand firm on issue of free speech. .. We are Americans .. Even if it's just dumb jokes in The Interview, we have the right to make them."
Comic host Bill Maher wrote on Twitter that condemning the Paris attack was not enough.
"Unless you strongly endorse the right of anyone to make fun of any religion/prophet .. you are not a moderate Muslim," he wrote.
British comic Ricky Gervais tweeted: "If I believed in an all-powerful God I'd also assume he could do his own murders."
Julianne Moore, using the trending hashtag #JeSuisCharlie ("I am Charlie"), wrote: "I am heartbroken by the loss of life and attack on freedom of expression."
Mark Ruffalo wrote: "What a tremendous loss. A free press is our greatest weapon against tyranny, home and abroad. #JeSuisCharlie."