A ten-year-old Hong Kong boy was confirmed yesterday to have developed kidney stones after drinking melamine-tainted milk, bringing the total number of Hong Kong children affected by such illness to five.

The Center for Health Protection, of the Department of Health of the Hong Kong Special Administrative Region (HKSAR) government, said it received notification on the case from the Hospital Authority, which runs the government-owned hospitals.

The boy lived in Hong Kong but also traveled to the mainland. It was reported that he used to consume milk products contaminated with melamine in Hong Kong and during his stay on the mainland, although he had no symptoms of kidney problems.

The boy was taken to a Hospital Authority special assessment center yesterday by his parent for a medical check-up and kidney stones were found in his left kidney.

He was hospitalized and now stable, the HKSAR government said.

The contamination incident has prompted Hong Kong health authorities to recall many related products and step up examination and checking efforts. Hong Kong also revised its food safety regulations to ban melamine in foods.