We have firsthand descriptions of biological weapons factories on wheels and on rails.

目击者描述说，他们看到过建立在汽车和火车上的生物武器工厂。

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U.S. Secretary of State Colin Powell in February told the United Nations Security Council that U.S. intelligence indicated Iraq had production facilities for biological weapons "on wheels and on rails, " and on at least 18 flatbed trucks.

CNN: U.S.: Mobile labs found in Iraq