NANCHANG - Commerce authorities in east China on Thursday said they were investigating a leading dairy company after claims that a baby died from drinking its milk formula surfaced on the Internet.

It is reported that a twin in rural Jiangxi province suffered from diarrhea and uncontrollable shaking after drinking milk formula of the Nasdaq-listed Synutra International, Inc. The baby boy died hours later in a pediatric hospital, according to widely viewed online post which quoted the twin's family.

Authorities have sealed the same batch of Synutra products in the county of Duchang, where the case was reported, and sent samples for testing, said officials with the county's bureau of industry and commerce.

The test results will be known on Friday, they said.

The mother of the twin Cao Haijuan told Xinhua that her son died in hospital late last Saturday hours after drinking Synutra's Youbo milk formula. He was buried on Tuesday while the daughter, who was also sick, was discharged from the hospital on Wednesday.

It is the latest scandal to hit Synutra after the melamine contamination more than three years ago.

The company said in an online statement that the actual cause of the baby's death remains unknown but baby formula does not normally cause any of the reported symptoms that are usually caused by flu or allergies.

Synutra said it offers its condolences to the baby's parents and has appealed to the Ministry of Public Security to launch a serious investigation and properly settle the issue, the statement said.

China's dairy industry suffered a heavy blow after a scandal in 2008 in which the baby formulas of many major dairy companies, including Synutra, were found to be tainted with melamine, an industrial compound used to create plastic and resin. The tainted formula led to the deaths of six infants and sickened 300,000 children across the country.

In 2010, Synutra's formula was accused of triggering sexual precocity among baby girls. But the allegations were found to be groundless after a probe by the Ministry of Health.