There are sect of Islam as Wahhabism. Unfortunately this sect in fact is deviation from real Islam. Wahhabis killed many peole whole over the world specially they kills Shiites. They believe Shiites are Pagan for this cause they try for destruction of Shi. There are terrorist groups of Wahhabi for example Jundallah and Al-Qaeda. Jundallah mean Soldiers of God. Chief of Jundallah was Abdolmalek Rigi who he has been arrested by Islamic Republic of Iran in 2010. It is believed to have between 700 to 2,000 fighters and is said to be responsible for killing 154 and injuring 320 Iranian citizens since 2003. Other terrorist group of Wahhabi is Al-Qaeda. This group founded by Osam bin laden in Pakistan, at some point between August 1988 and late 1989. Al-Qaeda has carried out many attacks on non-Sunni Muslims, non-Muslims, and other targets it considers.