Abu Ahmad (the later al-Muwaffaq) in command of an army and instructed him to fight against al-Musta'in and Muhammad. The army, consisting of five thousand Turkish and Ferghanan (Faraghinah) soldiers under the leadership of Kalbatikin al-Turki and two thousand North African (Magharibah) soldiers under the leadership of Muhammad b. Rashid al-Maghribi, departed Samarra on February 24. Six days later they arrived in Ukbara, where Abu Ahmad led the prayers in the name of al-Mu'tazz. The Turks and North Africans began looting the area between Ubkara and Baghdad, causing many of the local residents to abandon their estates and fields. On March 10, Abu Ahmad and his army appeared before the Shammasiyah gate on the East side of Baghdad, and the siege of the city began. Strategies and military strength Al-Musta'in Neither caliph participated in the direct military operations of the war. In Al-Musta'in's case, he was generally content to leave the responsibility of conducting the war effort to Muhammad b. 'Abdallah. As commander, Muhammad opted for an overall defensive strategy. Relying on his position in Baghdad, he was reluctant to engage in any sort of offensive operations outside the city and its surrounding districts, even when he was advised by others to do so. While he did make an effort to securing the nearby towns that controlled access to the city, there is no mention of any attempt to attack Samarra. By staying within Baghdad and keeping the city's supply routes open, while at the same time cutting off foodstuffs and tax receipts meant for Samarra, Muhammad likely believed that he could outlast al-Mu'tazz's armies. A massive amount of work was done to prepare Baghdad for a siege. Walls and trenches were constructed on both the east and west sides of the city, at a cost of over three hundred thousand dinars. Ballistas and mangonels were installed on the walls, and "war engines" designed to hinder enemy movement were placed in front of the city gates. The market awnings were removed so as to prevent them from being set on fire, and the areas outside the city were ploughed so that the mud would entrap the attackers. A few days after the fighting began, Muhammad ordered the razing of a large area behind the walls, so that the defenders would have more room to operate in. Muhammad had numerous sources of manpower in his allies and in the people of