BEIJING - The Golden Triangle, one of Asia's two major illicit opium-producing areas, is still the most harmful source of drugs in China, a report on the country's drug control situation said Tuesday.

Chinese police seized 5.1 tonnes of heroin and 7.9 tonnes of methamphetamine produced in, and smuggled from, the region last year, which made up 72 percent and 55 percent of the total nationwide seizures of heroin and methamphetamine, respectively, up 55 percent and 62 percent year-on-year, according to the report.

The report was delivered by Minister of Public Security Meng Jianzhu to the bimonthly legislative session which opened Tuesday, also the International Day Against Drug Abuse and Illicit Trafficking.

Police also uncovered 223 drug smuggling cases originating in the Golden Crescent area, another major Asian region for illicit opium production, in 2011, up nearly 30 percent year-on-year.

The Golden Crescent is located at the crossroads of Central, South and Western Asia, and includes Afghanistan, the world's largest opium producer, the report said.

It noted that the task of tackling drug trafficking has become increasingly arduous, as more cocaine from South America and methamphetamine from Northeast Asia have been smuggled into China.