Jafar ibn Ali al-Hadi

Abū ʿAbd Allāh Jaʿfar ibn ʿAlī al-Hādī, also derisively known as al-Kadhdhāb in Twelver Shi'ism, was the third son of the tenth Twelver Shi'a Imam, Ali al-Hadi. He claimed to be an imam and established his own sect of followers, to whom he was known as al-Zakī.