The substance V-1 Immunitor cannot be distributed or sold because it is not registered as an Aids drug or a food supplement, the Food and Drug Administration says.

FDA secretary-general Supachai Kunaratanapruk said the agency last year revoked a licence allowing the product to be marketed and sold as a food supplement.

The FDA revoked the licence after the manufacturers placed unauthorised advertisements.

The FDA said claims of the product's properties were exaggerated.

"The backers claim the product is an Aids cure, but it does not contain any medicinal properties. If it could really cure HIV/Aids, it would have been registered as a drug and not a food supplement in the first place," he said.

Magnesium chloride was named as the main ingredient in the licence application.

He has warned consumers, particularly people with HIV/Aids, against being lured into purchasing the substance in the belief it can cure the disease.

The clinic was selling the product, which comes in the form of a pill, for 30 baht a tablet and patients were told to take it twice a day.

The licence of the Chachoengsao plant making V-1 Immunitor has been temporarily held back and a ban imposed on production.

Dr Supachai was speaking after police and health staff raided Ban Bangpakong clinic on Saturday.

The ministry said it was being run as an illegal clinic.

Thares Saengsakul, the operator, and three staff were charged with providing medical treatment and extracting blood from patients, which is allowed only at licensed clinics. They were released on bail.

Although the Public Health Ministry does not allow V-1 Immunitor here, the substance has been flooding into Asian and African countries such as Malaysia and Swaziland.

In 2001, the product's backers distributed the product widely in Thailand, with the support of the Salang Bunnag Foundation, which later parted company with the manufacturers.