Iraqis are telling American troops about places where weapons of mass destruction might be hidden, adding to the thousands of sites the United States wants to check.

As combat winds down in Iraq, the hunt for chemical and biological weapons or nuclear materials is rising on the priority list for American troops. There are more potential nuclear, biological or chemical weapons sites in Iraq than U.S. military teams to check them, Pentagon officials said Sunday.

U.S. forces have a list of 2,000 to 3,000 sites in Iraq that need to be checked, and weapons teams are checking up to 20 sites a day, said the war's commander, Gen. Tommy Franks. Iraqis ranging from common citizens to high-ranking officials have suggested other possible hiding places to be searched, Franks and other military officials said.

"There are so many sites, we are not able to get to all of them right away," a senior Pentagon official said, speaking on condition of anonymity. "It's fair to say there are a lot of places U.S. forces are adding to the list."

Captured Iraqi officials could help add to the list as well. Several top officials of Saddam Hussein's regime in Iraq, including the president's half brother and a former science adviser, are in coalition custody.

The Iraqis are being interrogated about the country's suspected weapons of mass destruction programs, U.S. officials said. They also are being pressed for details on where Saddam is, if he is alive, as well as the whereabouts of other former Iraqi leaders.

The captured Iraqis include Watban Ibrahim Hasan, one of Saddam's three half brothers, who once served as Iraq's interior minister. Hasan was the five of spades in the deck of playing cards the U.S. military issued with pictures of wanted Iraqi officials.

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.

One former Iraqi official who could provide major help for the weapons hunt is Lt. Gen. Amer al-Saadi, who surrendered to American forces Saturday. Al-Saadi, the seven of diamonds in the U.S. deck of cards, was Saddam's point man on weapons of mass destruction before the Iraqi government collapsed.

Pentagon officials said they did not know if al-Saadi was sticking to his prewar assertions that Iraq no longer had any chemical or biological weapons. Shortly before leaving his Baghdad villa to surrender Saturday, al-Saadi insisted Iraq has no such weapons.

Also unclear was how helpful Hasan could be. He was dismissed as interior minister, the official in charge of Iraq's domestic security, and was shot by Saddam's son Odai in 1995 amid one of the many family squabbles.

Saddam did not trust Hasan and was having him watched, a U.S. official said. He was captured near Mosul in northern Iraq, apparently as he tried to escape to Syria, the official said.

Another half brother, Barzan Ibrahim Hasan, was targeted by a coalition airstrike Friday on a building in central Iraq. Military officials said Sunday they had not confirmed Barzan Hasan's fate.

American troops also have found scores of vests filled with explosives and metal bearings that could be used by suicide bombers in Iraq, Franks and Defense Secretary Donald H. Rumsfeld said. Documents found at one site suggested 30 of the bomb vests were missing, Rumsfeld said.

Franks said the United States has a DNA sample from Saddam to check against remains found that might be from the Iraqi president. Two Baghdad airstrikes targeted Saddam, but Rumsfeld and Franks said they did not know if Saddam was alive.

"He's either dead or he's running a lot," Franks said.

Pockets of resistance, as well as Fedayeen Saddam "death squads," remain in Iraq, Rumsfeld said.

"The war isn't over. There are still people being killed. We lost some people last night," he said.