Arab governments, Muslim leaders and organisations across the world have condemned the deadly attack in Paris. But it was praised by jihadi sympathisers who hailed it as "revenge" against those who had "insulted" the Prophet Mohammed.
Saudi Arabia called it a "cowardly terrorist attack that was rejected by the true Islamic religion". The Arab League also denounced the incident in which masked gunmen shouted "Allahu Akbar", which means "god is great" in Arabic. Iran, Jordan, Bahrain, Morocco, Algeria and Qatar all issued similar statements.
No organisation claimed responsibility for the attack but supporters of the Islamic State (IS) welcomed it on social media, using Arabic language hashtags including "our revenge for the messenger [Mohammad]", "Paris is Burning", and "Paris under Fire".
One Twitter user, apparently an IS supporter, said: "This is the first reaction. You'll not live in safety again."
A graphic posted by another supporter showed the black flag of IS flying over the Eiffel Tower, with the slogan in French: "We are everywhere."
Many Arabic Twitter users, however, attacked the terrorists, one pointing out that Charlie Hebdo had made fun of Jews, Christians and Buddhists without its journalists being targeted and murdered.
The Union des Organisations Islamiques de France, which represents more than 250 Muslim organisations, condemned the killings. Tariq Radaman, a leading Muslim thinker, commented: "It is not the Prophet who was avenged, it is our religion, our values and Islamic principles that have been betrayed and tainted."
Other Muslims said they would only condemn the Paris attack if France condemned the killings of Muslims worldwide.
Islam is not unique in taking offence to what it perceives to be blasphemy. Judaism forbids the use of "graven images" and Christianity has at times frowned on pictures of sacred figures, allowing only the cross to be depicted in churches.