After Saddam Hussein's (search) capture, another member of his governing elite has taken on the title of the Pentagon's most wanted: Izzat Ibrahim al-Douri (search).

The U.S. military appears to be on the trail of the Revolutionary Command Council's vice chairman. In a pre-dawn raid Wednesday, U.S. troops captured four of his nephews, who were believed to be actively helping him locate safe houses and transportation. The raid came less than two months after al-Douri's wife and daughter were arrested. They remain in U.S. custody.

A U.S. official, speaking on the condition of anonymity Wednesday, called al-Douri the single most significant regime figure still on the loose in Iraq. U.S. officials believe he has been active in the resistance, so "there is a good bit of attention on wrapping him up," the official said.

Nevertheless, it's unclear exactly what role al-Douri is playing within the insurgency, though he may be providing leadership or funding. His nephews have been detained for questioning.

Al-Douri was the vice chair of the Baath Party's (searchRevolutionary Command Council, the toppled government's highest ranking governing body. Saddam's longtime confidant is No. 6 in the U.S. list of the 55 most wanted Iraqis. The United States has put a $10 million bounty on his head.

Some Middle East experts say al-Douri was part of a small group of people who would execute Saddam's orders — kill this person, torture that person — and helped make Saddam a tyrant.

"He's a henchman. In every repressive authoritarian regime, there are people who execute the policies of a leader, and he was at the leader's side making the pronouncements and death sentences work," said Jon Alterman, Middle East Program director for the Center for Strategic and International Studies, a Washington, D.C., think tank.

Al-Douri was known for his carrot-red hair and, more recently, for an outburst at a summit of Muslim nations two weeks before the Iraq war. "Shut up, you monkey," he told a Kuwaiti minister who had called comments by al-Douri lies.

Richard Murphy, who met al-Douri once when he was assistant secretary of state during the Reagan administration, said such comments were an echo of Saddam's rhetoric. Still, Murphy said that some Arab leaders had some relative confidence in al-Douri.

"He had a knack for coming across as a dependable fellow," said Murphy, now with the Council on Foreign Relations in New York. For instance, during an Arab summit in Beirut in March 2002, an embrace between al-Douri and Saudi Crown Prince Abdullah sent shudders through Washington, Murphy noted.

Unlike other prominent members of Saddam's regime, al-Douri hasn't slinked away, been captured or killed, perhaps due to his background as an enforcer and security agent of the Saddam regime. Still, his health may make it difficult for him to avoid U.S. troops.

Al-Douri, in his early 60s, is believed to be suffering from lymphoma, but that has not been confirmed, the U.S. official said.

Prospects for his capture may be improving. Another defense official said that since Saddam's capture, the U.S.-led coalition has seen daily engagements with the insurgency drop from an average of 40 a day to less than 20, and it has noticed an increase in Iraqis who are cooperating and providing useful intelligence.

Still, "we are always hesitant to say it is a trend," the official said.