CBS News correspondent Mark Strassmann reports U.S. military sources in Baghdad are being extremely cautious about taking the reports of Abu Ayyub al-Masri's death at face value.
One senior commander told CBS News that reports of al-Masri's death or capture seem to come from Iraqi officials every month, and so far they have all been false alarms. U.S. Ambassador Ryan Crocker told reporters that American authorities in Baghdad were seeking more information.
An umbrella organization of Iraqi insurgent groups denied the al Qaeda leader had been killed, saying he was alive and safe, according to an Internet statement.
"The Islamic State of Iraq reassures the Ummah (nation) that Sheik Abu Hamza al-Muhajer, God protect him, is alive and he is still fighting the enemy of God," the umbrella group said on a Web site commonly used by insurgents.
A series of reports Tuesday said Abu Hamza al-Muhajer — whom U.S. and Iraqi forces identify by another pseudonym, Abu Ayyub al-Masri — had been killed, either by rivals in al Qaeda or Sunni tribesmen who have turned against al Qaeda.
A Pentagon spokesman, Col. Gary Keck, said he was aware of the reports from Iraq but had no confirmation.
"U.S. forces are working with Iraqi officials to determine if this is true," he said, adding that he did not know whether U.S. forces were at the site of the alleged killing.
In recent months, divisions among Sunni insurgent groups have sharpened, in part because of al Qaeda's attempt to dominate the "resistance," impose a harsh brand of Islam on ordinary people and use foreign fighters, U.S. officials say.
More than 200 Sunni Arab sheiks in Anbar province have decided to form a political party to oppose al Qaeda. Clashes have erupted in three Sunni provinces between al Qaeda and other insurgent groups, notably the nationalist 1920 Revolution Brigades, U.S. officers say.
Iraqi officials released conflicting accounts of when and where al-Masri was purportedly killed, and who was supposed to have killed him. It was also unclear whether Iraqi authorities had the body.
Chief government spokesman Ali al-Dabbagh Al-Dabbagh told Al-Arabiya television that the report of al-Masri's death was based on "intelligence information," adding that "DNA tests should be done and we have to bring someone to identify the body."
But he refused to say unequivocally whether Iraqi security forces had the body, citing security restrictions.
Just as al-Zarqawi's death did little to reign in al Qaeda in Iraq, CBS News terrorism consultant Paul Kurtz says al-Masri's demise, if confirmed, would likely have little effect on the group's deadly operations.
"Al Qaeda in Iraq is a multi-headed hydra," Kurtz, who used to work for the Bush administration in counterterrorism, said on CBS' Early Show.
Kurtz says the influence of the Iraq chapter of al Qaeda is believed to be "limited to the confines of Iraq," and the leader's death would have little or know effect on the group's worldwide operations. A State Department report released Monday said terror attacks across the world had increased 25 percent in 2006.
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