In 899, following the death of the previous leader of the sect at Salamiya, Sa'id ibn al-Husayn, the future founder of the Fatimid Caliphate, became the leader. Soon, he began making alterations to the doctrine, which worried Hamdan. Abu Muhammad went to Salamiya to investigate the matter, and learned that Sa'id claimed that the expected was not Muhammad ibn Isma'il, but Sa'id himself. This caused a major rift in the movement, as Hamdan denounced the leadership in Salamiya, gathered the Iraqi s and ordered them to cease the missionary effort. Shortly after this Hamdan "disappeared" from his headquarters at Kalwadha. The 13th-century anti-Isma'ili writer Ibn Malik reports the rather unreliable information that he was killed in Baghdad, while Ibn Hawqal, who wrote in the 970s, claims that he reconciled with Sa'id and became a for the Fatimid cause under the name of Abu Ali Hasan ibn Ahmad. According to Wilferd Madelung, given Ibn Hawqal's Fatimid sympathies and friendship with Abu Ali's son, "his information may well be reliable".
