By October 2006, small radicalized militias had seemed to overshadow the larger and more organized Sunni groups which had composed the insurgency previously. As disagreements emerged in pre-existing groups for reasons ranging from the rift in the Sunni forces between foreign and Iraqi fighters, competition between Mahdi Army and Badr Brigade, and anger over various decisions such as Muqtada al Sadr's agreement to join the political process, dozens of insurgency groups sprung up across the country, though particularly in Baghdad where the U.S. army has listed 23 active militias. Residents have described the capital as being a patchwork of militia run fiefs. As a result of the insurgency's splintering nature, many established leaders seemed to lose influence. This was particularly illustrated on 19 October, when members of the Mahdi army briefly seized control of Amarah. The attack, while demonstrating the influence of the Madhi army, is believed to have originated as a result of contention between local units of the Madhi army and the allegedly Badr brigade run security forces, and the timing suggested that neither Al Sadr nor his top commanders had known or orchestrated the offensive.