Four workers were killed while six others remain hospitalized after they were poisoned by carbon monoxide on Monday in eastern Jiangxi province. The incident happened in Jiangxi Yadong Cement Company in the city of Jiujiang, according to China\'\'s News Agency (Xinhua).A lack of oxygen was blamed, as the poisoned workers were working in a warehouse crammed with pulverized coal, said an official with the local information office, who cited an initial investigation. The Jiangxi Yadong Cement Factory, with annual production of 8 million tonnes of cement, is a joint-venture between Taiwan-based Far Eastern Group and Jiangxi Provincial Investment Group.