He participated as an Iraqi member delegation in the discussions conducted between Iraq and the United Nations and the IAEA for the period 1991-2003. He was number 49 on the US list of 55 most wanted Iraqis during the 2003 invasion of Iraq. He was the 13th on the list taken into custody on or around 26 April 2003. Before his capture, American intelligence agents had previously urged Amin to defect and provide the United States with key information on the Iraqi weapons program, as well as Saddam Hussein's inner circle. He was released from U.S. custody on 23 December 2005, despite the fact that weapons of mass destruction were in fact found and used against coalition forces. The first recorded case of a WMD being used was when an IED containing sarin gas, a nerve gas classified by the UN as