China has launched a nationwide investigation into all baby milk powders, saying those producing tainted powder "will face serious punishment".
A contaminant was found in one brand of formula and one infant died this week.
State media said the inquiry would seek to discover if the tainted formula led to the baby's death and caused kidney stones in dozens of other babies.
The new scare revived memories of a fake formula scandal four years ago in which at least 13 babies died.
One baby died on Wednesday in north-western Gansu province from kidney stones, a rare complaint in infants. More than 50 others have developed kidney stones there and in other provinces this year.
"[Authorities] in collaboration with local governments will determine the cause and the responsibility and severely punish those responsible," the health ministry said, according to state news agency Xinhua.
The Administration of Quality, Supervision, Inspection and Quarantine was responsible for the probe, it said.
Product recall
Investigations so far showed that most of the babies had drunk Sanlu brand formula and the company was recalling milk formula made before 6 August, Xinhua said.
It added that about 700 tonnes of powder contaminated with melamine - a toxic chemical used in plastics, fertilizers and cleaning products - were believed to be in circulation.
Correspondents' calls to the Hebei province-based dairy producer went unanswered. But a statement from the New Zealand-based dairy product company Fonterra Cooperative Group Ltd, a part-owner of Sanlu, confirmed the recall.
The company "has advised us that they have recalled product in China and have put new milk quality testing procedures in place," Fonterra said in a statement emailed to The Associated Press.
Melamine was "highly suspected" to have contaminated batches of Sanlu milk formula, China's Ministry of Health said late on Thursday.
Melamine has been used by Chinese suppliers of animal feed components to make them appear to have more protein. It was linked to the formation of kidney stones and kidney failure in pets in the United States last year, leading to thousands of deaths and illnesses.
A fake milk powder scandal in 2004 killed at least 13 babies in the eastern province of Anhui.
Investigators found that the milk given to these babies had no nutritional value, and the resulting scandal triggered widespread investigations into food safety.
^ Back to top | BBC Sport Home | BBC Homepage | Contact us | Help | ©
~RS~q~RS~~RS~z~RS~05~RS~)