U.S. intelligence in October 2005 published an intercepted letter purportedly from Ayman al-Zawahiri questioning AQI's tactic of indiscriminately attacking Shias in Iraq [REF].
In a video that appeared in December 2007, al-Zawahiri defended AQI, but distanced himself from the crimes against civilians committed by "hypocrites and traitors" that he said existed among its ranks [REF].