Police in northern China say they have arrested 27 people in their probe into tainted milk that has left tens of thousands of children sick.

The 27 are among 36 people detained since police in Hebei province started investigating San Lu Group, the company at the centre of the scandal, earlier this month.

It followed the discovery that the industrial chemical melamine, which is normally used to make plastics, had been added to San Lu powdered milk.

According to police investigations in Hebei, where San Lu is headquartered, the melamine was produced at underground plants and sold to breeding farms and purchasing stations.

Four babies died and more than 50-thousand infants needed medical treatment in China this month, and five children in Hong Kong, one in Macau, and four people in Taiwan have reportedly developed kidney stones after consuming tainted Chinese products.

South Korea finds more tainted products
South Korean investigators say they have found high levels of melamine in two more Chinese-made food products.

The Korea Food and Drug Administration says the chemical was found in Nabisco Ritz cracker cheese sandwiches, and in rice crackers made by Danyang Day Bright Co.

Melamine has now been found in six products imported to South Korea, including Misarang snacks made in China, and in Chinese-made non-dairy creamer imported from Hong Kong.

South Korea has banned imports of all Chinese-made food products containing powdered milk.

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