A cyanide spill in the Guijiang river near Wuzhou city in southwestern Guangxi province recently resulted in the death of a large number of fish in the river and suspension of water supply by some local water companies. The spill occurred when a truck carrying 10 tonnes of cyanide fell into the river and ruptured 19 of the 200 barrels it was carrying. One barrel of poison is still missing. However, officials claim that the spill had not affected any people. As a precautionary measure, authorities were screening fish and vegetables for traces of poison.

The Guijiang is a tributary of the Pearl river which flows through the densely-populated Guangdong province and into the South China Sea near Hong Kong and Macau. The water company in Macau had already stopped water imports from China and authorities in Hong Kong have launched cyanide checks. Macau has suspended water imports from China and also banned people from bringing in food from the Chinese mainland.