Samir Abd al-Aziz al-Najim was handed over to U.S. troops by Iraqi Kurds near the northern city of Mosul overnight, said U.S. Brig. Gen. Vincent Brooks.
Al-Najim was the Baath Party Regional Command Chairman for east Baghdad and was the four of clubs on the 55-card deck U.S. military officials handed out to American forces to help in identifying wanted Iraqi officials.
He was Minster of Oil until earlier this year and was Saddam Hussein's chief of staff for several years after the 1991 Gulf War.
He was the third member of the list of 55 captured thus far, and the second in as many days. Another one of the "most wanted" has surrendered and another is believed to have been killed.
Finding the leaders of the regime is a key goal of the U.S. campaign, both for its own sake and as an aid to finding weapons of mass destruction. Lower-level captures are also considered a possible link to higher-ranking fugitives, especially Saddam himself.
Central Command said Thursday that special forces troops had captured Barzan Ibrahim Hasan Al Tikriti, a half-brother and adviser to Saddam.
The first leader reported captured was Watban Ibrahim Hasan, one of Saddam's three half brothers, who once served as Iraq's interior minister.
Iraqi science adviser and special weapons chief Lt. Gen. Amer al-Saadi, surrendered over the weekend.
Ali Al Hasan Majid, known as "Chemical Ali" for his role in Iraq's alleged use of chemical weapons against Kurds in 1988, is believed to have been killed in an airstrike.
War commander Gen. Tommy Franks said Sunday that the United States was holding several high-ranking Iraqi prisoners in western Iraq. Neither he nor Pentagon officials would say how many leading Iraqis have been captured.
The biggest uncertainties concern the people at the top of the list: Saddam and his sons Uday and Qusay. It is not clear if they are alive or dead, in Iraq or elsewhere.
Barzan al-Tikriti, like his brother Watban, was seen as a major catch because of the likelihood he could provide information on Saddam's suspected weapons of mass destruction program, one of the major reasons the United States and Great Britain launched the war.
So far, coalition forces have not found any certain evidence that those weapons exist in Iraq.
The third half-brother, Sab'awi Ibrahim Hasan al-Tikriti, reportedly had taken refuge in Damascus, Syria. He is the six of diamonds in the 55-card deck carried by U.S. troops.
The United States has issued stern warnings to Syria not to harbor fugitives from the Saddam regime. Damascus denies any top officials of the former government have been offered sanctuary.
The U.S. also has in custody two important figures not on the list of 55.
One is, Jaffar al-Jaffer, a former nuclear program chief in Iraq, who had fled to an undisclosed Middle Eastern country before turning himself in to U.S. forces. Another is Abu Abbas, wanted for plotting the 1985 Achille Lauro hijacking, who was captured by U.S. forces in Iraq.
This week, American troops also raided the home of Dr. Rihab Taha, nicknamed "Dr. Germ," a microbiologist suspected of running Iraq's biological weapons program. Her whereabouts are unknown. She is not among the 55 wanted leaders.
Separately, a news report had said that Iraq's former information minister Mohammed al-Sahhaf may have killed himself. Al-Sahhaf was known for repeatedly denying during the war that the allied forces were making any progress.
Central Command says it's heard the reports, but hasn't confirmed them.