Rampant smuggling of synthetic drugs such as methamphetamine from Southeast Asia has led to more violent crimes nationwide, a senior official from the Ministry of Public Security said on Tuesday.

"China is facing a grim task in curbing synthetic drugs, including 'ice', which more and more of China's drug addicts tend to use," said Liu Yuejin, director of the ministry's Narcotics Control Bureau.

About 2.87 million people have been registered on suspicion of using drugs, according to the ministry.

"But the actual number of drug addicts is estimated at 14 million, five times more than our released official number, and about half have been suspected of taking methamphetamine," according to Liu.

He said that between January and September, police officers in 14 provinces and regions had uncovered more than 100 violent crimes caused by the abuse of methamphetamine, more than the total number in the previous five years.

"Compared with traditional drugs, such as heroine and opium, methamphetamine can easily lead to mental problems," he said. "Addicts will be prone to extreme and violent behavior, including murder and kidnapping."

Liu said that the estimate of annual economic losses caused by abuse of methamphetamine could be up to 500 billion yuan ($82 billion).

In recent years, a large amount of methamphetamine has been smuggled into China through border areas from Yunnan province to the Guangxi Zhuang autonomous region, said Song Zengliang, a senior police officer from the ministry's narcotics control department.

Last year, police in Yunnan province confiscated more than 9 tons of methamphetamine - 55 percent of the national total - that had been smuggled over the border with Myanmar. Cases of drug smuggling have also risen sharply on the border between China and Vietnam.

Song said China, Laos, Myanmar and Thailand have set up eight liaison offices at border areas to facilitate investigations. They have conducted more than 10 joint operations a year to fight drugs along the Mekong River.

In addition, annual meetings with other countries, including the United States, Russia, Myanmar and Vietnam, are helping combat the scourge, Song said.

Liu said China will further enhance judicial cooperation with other countries to collect more intelligence and focus on destroying the major drug-trafficking rings and capturing the main drug lords.

"The priority is to upgrade technical investigative means to collect more intelligence and strengthen judicial cooperation with other countries on anti-drug training and investigations," said Wu Ming'an, law professor from China University of Political Science and Law.

zhangyan1@chinadaily.com.cn