What's behind the anti-Charlie Hebdo protests?

A global anti-Charlie Hebdo campaign is getting bigger – and turning violent.

A week after an estimated four million people in France held peaceful rallies for freedom of speech in the wake of the Charlie Hebdo attack, Muslims around the world are expressing concern over what they see as continued disrespect for their religion.

“Many of France’s Muslims ... abhor the violence that struck the country last week,” The Washington Post reported. “But they are also revolted by the notion that they should defend the paper.”

Islamic extremists killed 12 people when they attacked Charlie Hebdo’s Paris offices for its publication of satirical cartoons of the prophet Muhammad, which Islamic dogma expressly forbids.

In the wake of the attack, millions in cities around the world rallied to defend freedom of speech, repeating the oft-cited saying, “I do not agree with what you say, but I will defend to the death your right to say it.”

In recent days, anti-Charlie Hebdo protests have erupted in response from those who believe that the magazine crossed the line with its cartoons and abused the right to free speech. The most violent occurred in Niger on Friday: Demonstrators set fire to a French cultural center and a number of churches, and five people are dead, reports The Independent.

On Saturday, police in Karachi, Pakistan fired water cannons and tear gas at an angry crowd rallying outside the French consulate there. A photographer for news wire service Agence France-Presse was shot and wounded, and four others were injured.

In Istanbul, demonstrators burned copies of a local newspaper that published translated versions of the Charlie Hebdo cartoons. Rioting also broke out at the end of a protest in Algiers, where demonstrators threw rocks, bottles, and fireworks at security forces. Rallies have also occurred in Yemen, Mali, Jordan, India, and elsewhere.

Not all displays of anti-Charlie sentiment have been violent, nor are Muslims the only ones who have expressed distaste for the magazine. Online, the hashtag #IAmNotCharlie has become a counter-tag to #JeSuisCharlie, or “I Am Charlie,” which took the the Internet by storm after the killings in Paris.

Others saw a double standard against Islam, citing France’s ban on publicly donning the full veil worn by conservative Muslim women. French law penalizes the wearing of clothing intended to conceal the face in public spaces.

Maurice “Sine” Sinet, a former Charlie Hebdo cartoonist who was allegedly fired by the magazine for anti-Semitism after he commented on the son of French president Nicolas Sarkozy, has become a central figure for the online campaign.

Pope Francis also appeared to weigh in on the side of the #IamNotCharlie campaign. While he condemned the Paris attacks, he told reporters on Thursday: "You can't provoke, you can't insult the faith of others, you can't make fun of faith.”

“Everyone has not only the freedom and the right but the obligation to say what he thinks for the common good,” he added. “[W]e have the right to have this freedom openly without offending.”