The head of Shanghai's anti-drugs commission, Xu Jinying, said that while most drug factories were in China's far south, the city was still facing a big problem.
The Chinese city of Shanghai has launched a major campaign against the production and use of synthetic drugs.
Officials are targeting night-clubs and other entertainment venues in an attempt to wipe out the trade in Ecstasy and Ice.
Ice is a Methamphetamine which is smoked and is highly addictive.
The move follows the closure of a number of clubs in the city in recent weeks as part of a national campaign against prostitution, drugs and gambling.
China's anti-drugs police warned earlier this year that they were finding it hard to cope with the quantities of drugs such as Ice coming onto the market.
The head of Shanghai's anti-drugs commission, Xu Jinying, said that while most drug factories were in China's far south, the city was still facing a big problem.
In recent years, Ecstasy - known in Chinese as "the head-shaking pill" - has become increasingly popular with young people on the city's fast-growing club scene.
Mr Xu said police were now planning to ransack entertainment venues.
He told the Shanghai Daily newspaper they would first target drug-users and then dealers in an attempt to wipe out the sources of drugs in the city.
Crackdown
Police in Shanghai are already reported to have closed more than 2000 bars and night spots in the last two months as part of a national anti-vice campaign.
Overall, State media say 80,000 people have been arrested across China since July on charges of prostitution, drug-use and trafficking and gambling.
The new drug crackdown is one of a series of such campaigns in recent years which have apparently had only limited success.
But several drug-traffickers have been executed this year in Shanghai alone.
Drug addicts are typically sent to rehabilitation centres.
Such establishments have been trying to shed their harsh reputation, which has tended to put many drug addicts off the idea of coming forward voluntarily.
The official national figure of 680,000 registered drug-users is thought to far under-estimate the true picture across China.