The leader of the Shi'ite Muslim group Hezbollah said on Friday that Islamist terrorists had done more harm to Islam than any cartoon or book, a reference to the attack by suspected Islamist militants on French satirical newspaper Charlie Hebdo.Sayyed Hassan Nasrallah said what he called "takfiri terrorist groups" had insulted Islam more than "even those who have attacked the messenger of God through books depicting the Prophet or making films depicting the Prophet or drawing cartoons of the Prophet."Takfiri is a term for a Muslim who accuses others, including another Muslim, of apostasy. Hezbollah considers members of ultra-hardline Sunni-dominated groups like al Qaeda and Islamic State to be takfiris.Twelve people were killed in the presumed Islamist militant attack on Wednesday at the weekly Charlie Hebdo, which has often lampooned Islam and other religions as well as politicians and other public figures.Cartoons in Charlie Hebdo have provoked angry reactions from some Muslims. Footage of the killings at the paper's offices showed gunmen shouting "we have avenged the Prophet Mohammad".Nasrallah was speaking to supporters in Beirut's southern suburbs via video link to commemorate the birthday of the Prophet.Hezbollah, which Washington describes as a terrorist group, functions as a political party that is part of the Lebanese government. It also has a military wing that has sent hundreds of fighters to support President Bashar Assad's forces in neighboring Syria.