Police have arrested a Chinese university professor who allegedly sold "millions of US dollars" worth of psychoactive drugs over the Internet to clients in the US, Britain, Canada and Australia, state media reported Tuesday.

The professor, surnamed Zhang, first learnt about the popularity of such drugs while teaching as a visiting academic in Australia, the official Xinhua news agency reported.

He then started a chemical company in 2005 but had staff manufacture "hundreds of kilograms" of methylone, commonly used as a substitute for MDMA, or ecstasy, the report said.

Between March and November last year, the business sold at least 193 kilograms of the substance to the overseas customers, Xinhua said.

The report did not provide a precise monetary figure, only quoting police as saying that Zhang earned "millions of US dollars" from the sales.

Xinhua dubbed Zhang "China's real-life Walter White" in reference to the fictional high school chemistry teacher and methamphetamine kingpin immortalised in the US hit cable TV series "Breaking Bad".

The report did not identify his university, only describing it as "famous" and in the central city of Wuhan.

Last month, police raided Zhang's lab in the city, where they found 20 kilograms of drugs and arrested eight people.

The report of Zhang's alleged dealings comes after police in May announced the arrest of a former chemistry professor on suspicion of selling a drug recipe to a gang which cooked up synthetic narcotics.

Chinese state media in May cited the government as saying the country has 14 million drug users, about one percent of the population, and their numbers have increased by an annual average of 36 percent in recent years.

Use of synthetic drugs, such as crystal meth and methcathinone, which can induce euphoric highs, are reported to be growing in rural areas of China.