Authorities are facing a "grim'' situation with the value of smuggled goods rising annually by about 20 percent from January to September, an official said.

Customs had uncovered 1,415 cases of smuggling by the end of September, involving goods worth 22.8 billion yuan ($3.66 billion). The value marked a 20 percent annual increase, according to the General Administration of Customs.

In 2011, authorities uncovered 1,776 smuggling cases involving products worth 28.77 billion yuan, up 14 percent over the previous year in terms of value.

Of this year's cases, 57 were categorized as serious as each involved goods worth more than 10 million yuan.

This figure represents a 29.5 percent increase from a year ago, according to authorities.

"We're facing a grim situation. The number and value of cases in China have been rising about 20 percent annually in the past three years," said Chen Jianxin, deputy director of the anti-smuggling bureau under the General Administration of Customs.

Smuggling can do huge harm to the economy, particularly when China is witnessing a slowdown in foreign trade.

China's trade reached $2.84 trillion in the first nine months of the year, up by just 6.2 percent year-on-year.

Electronic goods, chemicals, frozen meat and seafood, as well as luxury cars and car parts accounted for most of the seized products that had been brought into the country, Chen said.

Rare earths and precious artifacts account for most of the smuggled items leaving the country.

There has been a shift over the last 10 years away from non-luxury vehicles, oil and tobacco.

In the first nine months of this year, customs unearthed 549 cases involving drugs, protected animals, plants, weapons and ammunition, as well as solid waste.

These items accounted for 39 percent of all cases.

"Lower domestic tariffs and greater trade have slashed the profits for smuggling traditional tax-related products," Chen said.

"But the huge price difference in domestic and overseas markets for prohibited items remains."

Chen acknowledged that transport is a key focus in the campaign against smuggling.

In particular, smugglers are making use of residents, with multiple-entry passes, paid to repeatedly carry a small number of prohibited commodities each time through checkpoints, Chen said.

From March to August, Shenzhen, Guangzhou and Gongbei customs — all in Guangdong province — uncovered cases with a total value of 100 million yuan, and smashed 34 gangs, Chen said.

Police have opened special channels for multiple-entry passengers in Guangdong customs, according to Wang Zhi, deputy director of Shenzhen customs.

Chen also said shipping is often used to smuggle mineral products abroad, such as rare earths, and illegally carry hazardous items back to China, such as electronic or medical waste.

Authorities have cracked down against gangs in the Beilun River and the Beibu Gulf region in the Guangxi Zhuang autonomous region, as well as across the Pearl River in Guangdong province.

Hong Daode, a law professor from China University of Political Science and Law, also suggested more input into upgrading detection equipment at borders.

"As far as I know, only about 5 percent of all cargo in and out of China goes through custom checks. The rate should be increased," Hong said.

"But more inspections should not impair clearance efficiency. So we must rely on technological development, such as shared information systems and detection equipment at ports."

Contact the writer at zhangyan1@chinadaily.com.cn