Online scam

Illegal online pharmacies are more likely to sell counterfeit or substandard drugs than drug stores or hospitals, officials said.

Other problems the crackdown will look to tackle are retailers who are repackaging expired drugs, who are falsely marketing the efficacy of their products as well as the improper storage of drugs.

"Illegal online sales of drugs is actually a public nuisance for the world," Li said. "The price they offer might sound tempting but quite often scams are behind."

Last month, Li said, the US FDA shut down 1,677 websites for selling fake or substandard drugs.

But Mao said it is extremely difficult to crack down on online stores that sell illegal medicines, pointing out that some illegal websites may base their servers outside China.

Other online outlets like bulletin board systems, social networking tools and instant messaging services are also beginning to sell fake medicines, "making overhauls even more difficult", he said.

As part of the crackdown, the administration will target major TCM herbal markets on the mainland in late August.

Businesses caught with adulterating TCM herbs or ingredients as well as improperly processing, producing, selling and marketing poisonous medicinal materials will be shut down and punished, Mao said. Businesses also sourcing ingredients from plants and animals that are protected by China will also be shut down.