Diyar Ismail Mahmoud, known as Abu al-Afghani, was identified as the killer of the two soldiers, Iraqi National Security Adviser Mouwafak al-Rubaie told reporters. The two soldiers' mutilated bodies were found after they were taken prisoner following a clash near Youssifiyah.
A third American was killed in the clash.
Al-Rubaie did not say when Mahmoud was wounded or when he died.
The bodies of two soldiers from the 2nd Brigade, 101st Airborne Division were found on June 19 not far from a checkpoint on the Euphrates river south of Baghdad where they were abducted.
The discovery of Pfc. Kristian Menchaca of Houston and Pfc. Thomas Tucker of Madras, Ore. - both of whom were badly mutilated and at least one beheaded - came after exhaustive searches with thousands of soldiers fanning out in an area south of Baghdad known as the "Triangle of Death" because of frequent attacks.
A third soldier, David J. Babineau, 25, of Springfield, Mass., was found dead at the checkpoint where the soldiers were killed two days earlier.
The three had been assigned to the 1st Battalion, 502nd Infantry Regiment - the same unit as five soldiers and one former Army private who now face charges in the alleged rape and murder of a teenage girl in Mahmoudiya last March.
The Mujahedeen Shura Council, an umbrella of extremist groups, claimed in an Internet statement that the three soldiers were killed last month in retaliation for the rape-murder. U.S. officials say they have no evidence to substantiate the claim.
The killing of the Americans followed the June 7th death of al Qaeda in Iraq leader Abu Musab al-Zarqawi in a U.S. airstrike northeast of Baghdad. Mahmoud was a top al-Zarqawi lieutenant, al-Rubaie said.
Al-Rubaie also says security forces have detained the leaders of the Omar Brigade group, a wing of al Qaeda in Iraq that claims to have carried many deadly attacks throughout the country.
He identifies the group's leader as Jassim Mohammed, known as Abu Othman, his deputy Abu Aisha, in charge of financing the group, and Abu Ihab, in charge of recruitment. The fourth is Abu Islam, who is chief of religious affairs, al-Rubaie said.
"The Omar Brigade is one of the death squads," al-Rubaie said, adding that the group was responsible for the deadly bombing in Baghdad's eastern neighborhood of Sadr City on July 1 that killed 66 people.
Al Qaeda in Iraq announced last year that it had formed the Omar Brigade to fight the Shiite militias. The group claimed to have killed many Shiite militia leaders since then.
Al-Rubaie refused to say, for security reasons, where the alleged Omar Brigade suspects were detained. He says the operation was carried out by Iraqi and multinational troops.
"This is a major blow to al Qaeda itself because this is a division that was trying to drive a wedge between Shiites and Sunnis," he said.
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