Hossam Mohammed Amin, the chief Iraqi liaison with UN weapons inspectors, is in coalition custody, the US Central Command has announced.
Amin, the former Iraqi National Monitoring Director, was No. 49 on the US list of the 55 most wanted figures from the regime of Saddam Hussein.
No further details were released.
Amin, also known as Hossem Mohammed Amin al-Yasin, was the six of clubs on the US deck of cards listing the most wanted figures.
The general was among the key figures in Saddam's weapons programs and would have detailed knowledge of any illegal armaments, if Iraq still posses them.
For more than a decade as head of the monitoring commission, the former air force communications engineer has earned a reputation as a loyal officer who has fulfilled Saddam's expectations.
Amin and his troops refused to allow U.N. inspectors into presidential palaces and other "sensitive sites" during the first round of U.N. inspections that ended in 1998.
He was also one of the few Iraqis authorized to comment on weapons of mass destruction. Like most of Saddam's most trusted lieutenants, he is from a prominent Sunni Muslim family from northern Iraq, in Mosul.
Early in his career, he was assigned to different air bases and radar installations. His career took off when Saddam established the military's Technical and Scientific Committee, a weapons research and development think tank, in 1980.
Others on the committee included Gen. Amer Rashid, Iraq's minister of oil, and Amir al-Saadi, Saddam's senior weapons adviser who is also in coalition custody. The committee was later expanded into the Military Industrialization Organization which produced all of Iraq's most lethal weapons.
Amin was also believed close to Saddam's son Qusai, who was the commander of the Republican Guard, and Saddam's personal secretary, Gen. Abide Hmoud.
That made Amin one of the best-connected insiders in the Iraqi ruling establishment.
Amin was also believed to have been among the Iraqi officials the Baghdad government claimed were encouraged by US intelligence agents to defect last year.
Iraq claims the attempt was made when an Iraqi delegation traveled to Vienna, Austria, last year to discuss the resumption of weapons inspections with UN officials.