The top U.S. commander in Iraq said he believes he knows who kidnapped three U.S. soldiers last weekend and that at least two of them are still alive, the Army Times newspaper reported.

"We know who that guy is," Gen. David Petraeus said in an interview posted Saturday on the Army Times Web site. He 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."

U.S. forces have been searching for the three since they went missing May 12 after a pre-dawn attack on their observation position about 20 miles south of Baghdad. Four U.S. soldiers and an Iraqi were killed in the attack.

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."

Petraeus spoke with the Army Times late Friday, his staff said.

According to the Army Times, Petraeus said an informant passed on the information about 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."

An Iraqi army intelligence officer involved in the search for the kidnapped U.S. soldiers told The Associated Press that two men detained during the sweep have confessed that they took part in the attack.

The two captives said there were 13 men involved in the assault and they split into two groups afterward, with the ringleader taking the kidnapped soldiers with his band of men. The two men said they did not know where the soldiers had been taken, according to the Iraqi intelligence officer, who spoke on condition of anonymity because he was not authorized to release the information.

The two men also told U.S. forces the location of the weapons cache used in the attack. The U.S. military later confiscated a large number of weapons at the site, the intelligence officer said.