The United Nations says increased trafficking and use of amphetamine type stimulants, or ATS, as well as the illicit production and abuse of drugs is a growing problem in Asia.

In its global drug report released Tuesday, the U.N.'s Office on Drugs and Crime says the trend is especially troubling in China and South East Asia. The agency says Asia accounts for about half of the world's ATS users. Opium production in the region also is on the rise, but opium production and use in the rest of the world has largely stabilized.

The report says the use of synthetic and prescription drugs, such as Ketamine, has increased, especially in China, including Hong Kong, as well as in Malaysia and Vietnam.

The report notes that users in Brunei, Japan, the Philippines and South Korea commonly abuse crystalline methamphetamine. Bhutan and Sri Lanka showed an increase in the use of cannabis and ATS, while in Bangladesh, ATS use has become “widespread.”

The study says that as the number intravenous drug users in the region increases, the risk of transmitting HIV, the virus that causes AIDS, also is on the rise.