back the forces. The Marines were ordered to stand-down and cordon off the city on April 30, where they would remain in a perimeter around the city for the following six months. A compromise on April 30 was reached in order to ensure security within Fallujah itself by creating the "Fallujah Brigade", a unit that drew from former members of Iraq's Army, local volunteers, and even the insurgents themselves. The unit's formation was part of a truce negotiation. This unit was to act under the control of the Coalition Provisional Authority, patrol alongside the Iraqi Police and National Guardsmen but maintain its autonomy. The Fallujah Brigade had many former Saddam loyalists. From various reports, Brigade members re-integrated themselves into the insurgent outfits that dominated. The city remained under the control of insurgent and rebel forces. Reportedly, Abu Musab al-Zarqawi's organization was among the several that exercised some authority in the area. By the end of the spring uprising, the cities of Fallujah, Samarra, Baqubah, and Ramadi had been left under Sunni guerrilla control with American patrols in the cities ceased. The insurgency had undergone another major shift, as insurgent organizations now had safe havens in cities such as Fallujah to develop and coordinate with each other. Zarqawi's group and its allies were in a period of uneasy cooperation with other insurgent groups dominated by nationalist and Ba'athist agendas, although the groups increasingly came into competition for territory within Sunni insurgent-controlled areas. U.S. forces launched only occasional armored forays into Samarra and Baquba, while about half a dozen small forts were maintained by the U.S. Marines in Ramadi, with the surrounding territory in the city controlled by rebels. American ground forces remained outside of Fallujah, though regular air strikes were conducted on alleged safehouses of Abu Musab al-Zarqawi's followers in the city. With the battle for Fallujah over, the Sunni insurgency continued against the U.S. forces remaining outside these cities as the guerrillas resumed their tactics of using IED's and mortars to attack U.S. forces indirectly, for the most part avoiding direct combat. Meanwhile, the fighting continued in the Shiite south. Over the next three months, over 1,500 Mahdi Army militiamen, several hundred civilians, and dozens of coalition soldiers were killed as the U.S. gradually took back the southern cities. On June 6, a truce was reached, temporarily ending the fighting. Sadr entered into negotiations with the provisional government to lay