As al-Mansur's persecution intensified, pressure began to mount on the brothers to react. Kufa, the traditional Alid base, was kept under close surveillance by the Abbasid government, and the two brothers resolved to launch a simultaneous rebellion in Basra and Medina.[1][2][3] Although the Alids could count on a large network of sympathizers throughout the Caliphate, the action was rushed and lacked organization.[4][11]