US applauds move to control killer narcotic

A top US drug enforcement official has praised China's ban on the opioid carfentanil, an elephant tranquilizer 10,000 times more potent than morphine, and three related synthetic opioids.

The Ministry of Public Security said on Thursday that carfentanil - along with furanyl fentanyl, acryl fentanyl and valeryl fentanyl - will be added to its list of controlled substances from March 1.

Fentanyl is used legitimately in hospitals as an anesthetic or for long-term pain management, such as in the form of prescription patches for late-stage cancer patients, according to Hua Zhendong, deputy director of the ministry's drug testing laboratory.