Health officials acting on a tip-off raided a food-processing plant in the south-western city of Chengdu last week, to discover that workers were using their teeth to debone chicken feet of meat intended for sale to restaurants.

The officials' report explained that they entered the plant to find two women gnawing at chicken claws beside a basket full of bones.

One worker told the officials that the act of deboning by teeth was an efficient procedure. Common practice at the plant was for workers to half-boil the feet in water, slit along three spots with a knife then remove the bones with their teeth. It only takes four to five seconds for a fast worker to debone one foot, meaning that it is possible to "process" over 100kg of chicken feet every day.

The officials have now closed the plant however and are trying to locate its owner. They confiscated over 250kg of chicken feet after discovering traces of saliva. Some of the workers carried Hepatitis B, which can be spread by body fluids.