retreat. As soon as Khalaf's army had been dismissed, however, Abu'l-Husayn Tahir returned, forcing Khalaf to seek Samanid help again. The conflict suddenly ended with the death of Abu'l Husayn Tahir in 970; his son Husayn declared his allegiance to the Samanids and left Sistan for the time being. Conflict with Husayn b. Abu'l-Husayn Tahir Within a year of the death of Abu'l-Husayn Tahir, his son Husayn pressed his claim to the amirate. Returning to Sistan, he soon gained control of Zarang in late 970/early 971. When Khalaf and his forces advanced to retake the capital, Husayn left the city and led his army against him. In the ensuing battle, Khalaf was victorious and several of Husayn's military commanders were killed. Khalaf retook Zarang in April 971 and immediately began to root out Husayn's supporters in the city, causing many of them to flee to Khurasan. Khalaf's victory proved to be only temporary, as Husayn returned in the following year. With an army that included elephants, Husayn defeated Khalaf in battle and reoccupied Zarang. A further setback for Khalaf occurred when the Samanids decided to get involved in the conflict. Khalaf had neglected to send the customary tribute to the Samanid amir at Bukhara, and Husayn took advantage of the amir's interest in the conflict by leaving Zarang and travelling to Bukhara to seek assistance (Khalaf, for his part, seems to have been more friendly to the Buyids, even including the name of the Buyid amir 'Adud al-Dawla in the khutba at one point, perhaps in an attempt to receive military aid. No record of Buyid intervention in Sistan during this time appears, however). A Samanid army was sent to support Husayn; Khalaf gave battle but was defeated in August of 979. Husayn and his Samanid allies then surrounded Zarang, which Khalaf had fled to after the battle. A siege lasting for probably three years began. Khalaf's forces attempted numerous sorties but were unable to break the siege; the Samanid and Saffarid armies battled each other several times, with neither gaining a decisive victory. The Samanid amir eventually sent a member of the Simjurid family, Abu'l-Hasan Muhammad Simjuri, to break the stalemate. With his help, a truce was achieved between Husayn and Khalaf in 983. Husayn received Zarang and much of Sistan; he entered the capital and had the name of the Samanid amir inserted in the khutba there. Khalaf