TOKYO -- Diet supplements manufactured in China have made 124 people ill in Japan, including four who later died, according to a government survey released at the weekend.

But private surveys suggested the number of victims might be much higher.

The Health, Labor and Welfare Ministry survey found that Chinese-made slimming products, including Yuzhitang and Xianzhisu, had made 124 people sick, including the four who died.

It did not say which period the survey covered, but on July 12 the Health Ministry first announced that 11 women had suffered health problems due to the diet products and another had died.

A survey by the **** Mainichi Shimbun **** newspaper had a higher toll.

The paper said Sunday it had counted 168 people who had suffered ill effects from the weight loss products, including four who died.

The influential **** Asahi Shimbun **** newspaper said Saturday its poll showed 158 people, including four who died, had experienced health problems related to the diet products.

And the **** Kyodo News **** said its survey found 171 people had suffered health problems due to the products.

Most of the victims suffered liver disorders, the government and the news organizations said.

The Chinese-made slimming pills made headlines this month after the ministry announced a 60-year-old woman had died and 11 others had suffered liver disorders after taking the products, which contain tea leaves and herbs.

The woman bought Yuzhitang through an import agency in February and started complaining about lassitude and nausea about one month after taking the diet aids.

On Friday, a fourth death linked to the diet supplements was uncovered as fears of side effects from the slimming pills spread across the nation.

The government vowed to tighten controls on health food products.

Health Minister Chikara Sakaguchi is quoted by AFP as saying he planned to investigate the shipping channels of slimming aids from other countries and strengthen a system to ban and collect unauthorized products.