US regulators have issued alert on milk products imported from China, including candy, snacks, bakery products, pet food and others for likely contamination.
Chinese products that contain milk will be detained at the border until tests prove that they do not contain toxic melamine and other contaminants, the US Food and Drug Administration said.
The products will not be released until the manufacturer or its customer gets them tested and they are found to be free from contamination, or show documentation indicating that the product does not contain milk or milk-derived ingredients.
The FDA move follows concern that these products could be contaminated with the toxic chemical melamine, which had caused the death of several infants in China.
Infant milk formula containing toxic melamine had resulted in the death of at least four infants in China. It had also left more than 50,000 other infants sick.
Melamine was also found present in a wide range of other products, including milk, eggs and fish feed.
Suppliers in the United States have recalled several products generally sold in Asian specialty stores, including a non-dairy creamer and Mr Brown brands of instant coffee and tea.
''We're taking this action because it's the right thing to do for the public health,'' said Steven Solomon, a deputy associate FDA commissioner.
But consumer advocates said the agency's action was too little and too late.
The FDA alert said traces of melamine and cyanuric acid, another contaminant, have been detected in ''a number of products that contain milk or milk-derived ingredients, including candy and beverages.'' FDA said inspectors in more than 13 other countries have also discovered melamine in Chinese products, including milk, yogurt, frozen desserts, biscuits, chocolates and cookies.
Melamine is added to milk and other products to artificially inflate protein levels. The product, however, dissolves poorly and may block the body's filtering system, potentially leading to kidney failure and death.