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"The amount of drugs seized accounts for 80 percent of the national total during this period," Sun Dahong, deputy director of the Yunnan Provincial Public Security Administration.

Police seized 3.87 tons of heroin, 3.71 tons of methamphetamine, or "ice", 1.38 tons of opium and 0.64 ton of other drugs, said Sun.

They arrested 11,976 drug-related suspects, including 35 listed key drug dealers, in the 9,959 drug trafficking cases, said Sun.

Bordering Laos, Myanmar and Vietnam, Yunnan has faced a major problem with drug trafficking from the Golden Triangle, a notorious drug-producing area along the Mekong River delta, including Myanmar and Laos.

Last year, Yunnan authorities seized more than 4,000 kg of drugs and arrested 4,600 suspected drug dealers. China seized 6.9 tons of heroin and 5.5 tons of "ice" in 2005.