American officials were hoping the latest Iraqis captured might provide information about Saddam's regime and its unconventional weapons programs, though former Iraqi leaders previously taken into custody have largely continued to deny the country had such weapons.
The scientist, Dr. Rihab Rashid Taha, had been negotiating her surrender for days and turned herself in over the weekend, said Maj. Brad Lowell of the U.S. Central Command.
U.N. weapons inspectors nicknamed Taha "Dr. Germ" because she ran the Iraqi biological weapons facility where scientists worked with anthrax, botulinum toxin and aflatoxin. A microbiologist, Taha holds a doctorate from the University of East Anglia in Britain.
Also reported captured was Armed Forces Chief of Staff Ibrahim Ahmad Abd al Sattar Muhammad al Tikriti, Pentagon officials said, citing initial reports from the region. He is No. 11 on a list issued last month of the 55 most wanted former members of Saddam's regime and the jack of spades in a card deck issued to troops looking for regime leaders.
No details of his capture were available.
Taha is not on the list of the 55, but among 200 Iraqis that Defense Secretary Donald H. Rumsfeld has said are sought but who have not all been named publicly.
Taha once said in a radio interview that Iraq was justified in producing germ weapons for its self- defense.
American forces have been trying to capture her and last month raided her Baghdad home, carrying away boxes of documents but not finding her or her husband.
Taha is married to Amer Rashid, who held top posts in Saddam's missile programs and was oil minister before the war. Rashid surrendered to U.S. forces April 28, 12 days after that Baghdad raid. The couple was married in 1994 and has a young daughter.
Rashid was the six of spades in the deck of cards.
With her detention, the United States has now acknowledged capturing at least 21 of the 55 most wanted; at least one is believed to have been killed in an air strike.
Iraqi leaders captured to date include:
No. 10 Muzahim Sa'b Hassan al-Tikriti, who headed Iraq's air defenses under Saddam.
No. 16 Abdel Tawab Mullah Huweish, director of the Office of Military Industrialization and a deputy prime minister in charge of arms development.
No. 18 Muhammad Hamza al-Zubaydi, former member of Iraqi Revolutionary Command Council and central Euphrates regional commander. Played key role in brutal suppression of Shiite Muslim uprising of 1991.
No. 21 Gen. Zuhayr Talib Abd al-Sattar al-Naqib, former head of the Directorate of Military Intelligence.
No. 24 Samir Abd al-Aziz al-Najim, senior figure in Saddam's Baath Party.
No. 32 Ghazi Hammud, Baath regional chairman in the Kut district.
No. 40 Jamal Mustafa Abdallah Sultan al-Tikriti, Saddam's son-in-law and deputy head of the Tribal Affairs Office.
No. 41 Mizban Khadr Hadi, appointed commander of one of four military regions Saddam established on the eve of the war.
No. 42 Taha Muhie-eldin Marouf, only Kurd among Saddam's hierarchy and one of Saddam's two vice presidents.
No. 43 Tariq Aziz, former deputy prime minister.
No. 44 Walid Hamed Tawfiq al-Tikriti, former governor of Basra province and member of Saddam's clan.
No. 45 Hikmat Mizban Ibrahim al-Azzawi, finance minister and deputy prime minister.
No. 47 Amer Mohammed Rashid, oil minister and a former general who led Iraq's top-secret missile program.
No. 48 Muhammad Mahdi al-Salih, former trade minister.
No. 49 Lt. Gen. Hossam Mohammed Amin, national monitoring director.
No. 51 Watban Ibrahim Hasan al-Tikriti, Saddam's half brother.
No. 52 Barzan Ibrahim Hasan al-Tikriti, another half brother of Saddam.
No. 53. Huda Salih Mahdi Ammash, a top biological weapons scientist known as "Mrs. Anthrax" and the only woman on the list.
No. 54 Abd al-Khaliq Abd al-Gafar, Iraq's minister of higher education and scientific research.
No. 55 Lt. Gen. Amer al-Saadi, who officials say led Iraq's unconventional weapons programs.
No. 5, Ali Hassan al-Majid, known as "Chemical Ali," is believed to have been killed.