 Complete the following phrase:  Some former members of the group were later linked to the assassination of Anwar Sadat in 1981. According to Paul Wilkinson, Shukri Mustafas execution ushered in the emergence of two wings within Al Takfir: one under the leadership of Abbud al-Zammut considered one of the original founders and one under the leadership of Ayman Al-Zawahiri, later second in command of al-Qaeda. Takfir wal-Hijra grew substantially through the 1990s as Afghan Arabs returned from Afghanistan to their homes in the Middle East and North Africa and spread their doctrines, establishing a decentralised network of believers that has been active throughout Algeria, Jordan, Lebanon, Libya, Morocco, Pakistan and Sudan. During the 