The Abbasids were concerned about the threat the Saffarids posed, especially after Ya`qub conquered Fars from Muhammad bin Wasil in 875. From Fars Ya`qub moved on to Khuzistan, taking possession of Ramhurmuz in December of 875. This move put the Saffarid army close to Iraq. It also put Ya`qub close to the Zanj revolt; the Abbasids feared that the Saffarids and Zanj would band together against the caliphate, although Ya`qub's later rejection of an offer by the Zanj to become allies casts doubt on this possibility. In any case it was an alarming development, as the caliph did not feel that he had the resources to stop Ya`qub. All of Ya`qub's supporters in Baghdad, who had been imprisoned in 873 following his conquest of Khurasan, were released, and al-Mu'tamid sent an embassy to Ya`qub to grant him the governorships of Khurasan, Tabaristan, Fars, Gurgan, and Ray, as appoint him as head of security in Baghdad.