Rafid Ahmed Alwan al-Janabi, known by the Defense Intelligence Agency cryptonym "Curveball", is a German citizen who defected from Iraq in 1999, claiming that he had worked as a chemical engineer at a plant that manufactured mobile biological weapon laboratories as part of an Iraqi weapons of mass destruction (WMD) program. Alwan's allegations were subsequently shown to be false by the Iraq Survey Group's final report published in 2004.

During the lead-up to the Iraq War, the United States had alleged that Iraq owned bioreactors, and other processing equipment to manufacture and process biological weapons that can be moved from location to location either by train or vehicle. Subsequent investigations failed to find any evidence of Iraq having access to a mobile weapons lab.