"We know who that guy is," Gen. David Petraeus said in an interview posted Saturday on the Army Times Web site.
Petraeus did not give the man's name but described him as "sort of an affiliate of al Qaeda. He's the big player down in that area. We've tangled with him before."
According to the newspaper, Petraeus said he did not know for certain whether the three 10th Mountain Division soldiers were alive.
"As of this morning, we thought there were at least two that were probably still alive," he said. "At one point in time there was a sense that one of them might have died, but again we just don't know."
Col. Steve Boylan, a spokesman for Petraeus, told CBS Radio News on Saturday that one of the missing soldiers may have died after being captured.
"We are getting indications that there is a possibility that one of the soldiers may have died after capture, at some point, but it is not definitive yet," Boylan said. "We do believe, based on various sources, that at least two of the soldiers are alive. But we are going with the assumption, and will continue to go with the assumption until proven otherwise, that all three are still alive."
An Iraqi army intelligence officer said two men have confessed to taking part in last weekend's attack.
The Iraqi official says the two captives say 13 men took part in the assault. He says they split into two groups afterward, with the ringleader taking the kidnapped soldiers with his band of men. The two say they don't know where the soldiers were taken.
U.S. soldiers widened the search for three missing American soldiers, detaining nine people in a raid Saturday about 25 miles from where the service members were taken captive, the U.S. military said.
The raid occurred in Amiriyah, a longtime Sunni insurgent area along the Euphrates River west of Baghdad, the U.S. said in a statement. The soldiers are from he 2nd Brigade Combat Team of the 10th Mountain Division at Fort Drum in northern New York.
The statement said the Amiriyah raid was part of a move to "follow tips and information leads in the disappearance of three U.S. soldiers."
Tribes in the Amiriyah area are related to those who live close to where the soldiers were seized May 12.
In addition, U.S. troops arrested two people in Baqouba "associated" with the al Qaeda command network, the U.S. said. Baqouba is 35 miles northeast of Baghdad, and it was unclear whether their arrests were directly related to the search for the missing soldiers.
The focus of the search is around the village of Quarghuli, 12 miles south of Baghdad, where the soldiers were captured following an attack on their observation post.
Four American soldiers and one Iraqi were killed in the attack.
An al Qaeda-linked group has claimed responsibility for the attack and the kidnappings.
According to the Army Times, Petraeus said an informant passed the information on who probably led the attack.
"Somebody's given us the names of all the guys that participated in it and told us how they did it, and all the rest of that stuff," he said. "Now, we have to verify that at some point in time, but it sounds spot on. We've had all kinds of tips down there. We just tragically haven't found the individuals."
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