Nevertheless, al-Mu'tasim's hold on the throne was still shaky, and he abandoned Ma'mun's campaign; the new base at Tyana was razed, and the still restive army returned to the Caliphate. Despite his acceptance of his uncle's succession, Abbas was removed from his governorship of the frontier lands, but retained the support of several leading figures in the Abbasid court. He soon became the focus of the factions opposed to al-Mu'tasim, and in particular his increasing reliance on, and favour shown to, his Turkish slave-soldiers ("ghilman"). This discontent resulted in an alleged conspiracy led by the general Ujayf ibn Anbasa which aimed to kill al-Mu'tasim and place Abbas on the throne. The plot was reportedly uncovered while al-Mu'tasim was campaigning against the Byzantines in 838, with the Caliph informed of it just after the celebrated Sack of Amorium. The resulting investigation, headed by al-Mu'tasim's trusted Turkish general Ashinas, resulted in the execution of most conspirators. This was broadened into a virtual purge of the army, in which the hitherto dominant Khurasani element was replaced with al-Mu'tasim's favoured Turks. According to al-Tabari, Abbas confessed to knowing of the plot while drunk. He was imprisoned at Manbij by another of al-Mu'tasim's lieutenants, al-Afshin, who executed him by a slow and torturous way: Abbas was fed very salty food, denied water, and exposed to the sun wrapped in a felt blanket, until he died. This led to a major purge of the traditional establishment that had served the Abbasids until then: alongside al-Abbas, over 70 other commanders were executed. His four brothers by Sundus were imprisoned by the Turkish commander Itakh in the latter's basement, and were never seen again. while Abbas' male descendants were imprisoned and executed by Ashinas. Some of his male Descendants Fled to Persia where they Gain Support from Persian Factions until the Mongol invasion of Iran.There Descendants Lived today in Khorasan.