Police in Yongjia County of east China's Zhejiang Province reported on Sunday that 30,000 tonnes of chicken feet polluted with hydrogen peroxide had been seized after police busted nine factories in the provinces of Jiangsu, Anhui, Henan and Guangdong.

The tainted snacks were first found in Yongjia last September and police followed the clues to break 35 "national sales networks." The factories used hydrogen peroxide solutions as bleach and antiseptics. Police are still hunting 11 suspects.

Hydrogen peroxide has a wide use in manufacturing and medical sectors as a disinfectant and bleach but could be detrimental to health if mixed with food.

Zhejiang Province is a main production base for Chinese chicken delicacies including feet, legs and heads. However, the industry has been embroiled in scandal after many factories were found to be adding excessive chemicals in processing stale chicken.