SINGAPORE -- The Singapore importer of a diet pill linked to a series of side effects, including one death, has broken a long silence on the health scare saying he had no idea how the tablets came to be adulterated.

Semon Liu said it was unlikely the "Slim 10" pills were tampered with in Singapore and the Chinese manufacturer had denied using the drug fenfluramine in its recipe, **** The Straits Times **** reported Saturday.

Liu had sent samples of the pills to Singapore health authorities from before they went on sale last December through April when abnormalities were found, the newspaper said.

One 43-year-old woman who took "Slim 10" has died of liver failure, another required a life-saving liver transplant and at least 14 others have reported illness.

"Never, beyond my wildest imagination, did I think it would end up like this," AFP quoted Liu as saying in his first interview since the controversy broke.

"I don't know how this could have happened. I can't believe it." Liu said he had been introduced to the pills by a Chinese friend in 1999 and took them himself for two years, losing 60 kilograms (132 pounds).

"I understood them to be 100 percent herbal, made from a Chinese recipe which was supposed to cleanse your body, and help the body burn fat faster," he said.

"So, the worst thing that could happen from taking them was diarrhea." His company, Health Biz, was told in early April to withdraw "Slim 10" from the market when batches were found to contain nicotinamide and customers were reporting adverse reactions.

At the end of the month, the Health Sciences Authority (HSA) said it had found fenfluramine in the tablets.

In light of the health scare, medical watchdog HSA has now asked all doctors in Singapore to run checks on patients who took the "Slim 10", with follow up tests a month later even if the first proved negative.

About 20,000 bottles containing 120 pills each were sold in diet-conscious Singapore during "Slim 10's" brief four months on sale.

Liu and Health Biz each face eight charges of contravening the poisons act and will appear in court next week.

The charge carries a maximum penalty of a 10,000 Singapore dollar (5,590 U.S.) fine and a two-year jail term.