Rescuers clad in protective outfits rush to search the source of a chlorine gas leak during a "Zhongshan-2007" anti-chlorine gas leak emergency drill in Lianyungong, East China's Jiangsu province April 15, 2007. More than 200 personnel from public security bureaus, firefighting departments, armed police bureaus and environmental protection agencies take part in the drill. [Newsphoto]

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