This image provided by the U.S. military on Sunday, Feb. 11, 2007 shows what officials say are Iranian 81mm mortar tail assembly fragments. U.S. military officials on Sunday accused the highest levels of the Iranian leadership of arming Shiite militants in Iraq with these and other sophisticated weapons. (AP Photo/U.S. military)
This image provided by the U.S. military on Sunday, Feb. 11, 2007 shows what officials say are Iranian anti-tank rocket propelled grenades. U.S. military officials on Sunday accused the highest levels of the Iranian leadership of arming Shiite militants in Iraq with these and other sophisticated weapons. (AP Photo/U.S. military)
This image provided by the U.S. military on Sunday, Feb. 11, 2007 shows what officials say is an Iranian 81mm mortar. U.S. military officials on Sunday accused the highest levels of the Iranian leadership of arming Shiite militants in Iraq with this and other sophisticated weapons. (AP Photo/U.S. military)
This image provided by the U.S. military on Sunday, Feb. 11, 2007 shows what officials say is a passive infrared trigger tied to Iran. U.S. military officials on Sunday accused the highest levels of the Iranian leadership of arming Shiite militants in Iraq with this and other sophisticated weapons. (AP Photo/U.S. military)
This image provided by the U.S. military on Sunday, Feb. 11, 2007 shows what officials call 'explosively formed penetrators,'or EFPs. U.S. military officials on Sunday accused the highest levels of the Iranian leadership of arming Shiite militants in Iraq with the sophisticated armor-piercing roadside bombs that have killed more than 170 American forces. (AP Photo/U.S. military)