China's latest crackdown on gun and explosives crimes aims to further curb the manufacturing, smuggling and online sale of firearms and explosives because such crimes remain prominent factors threatening public security, officials from the Ministry of Public Security said on Thursday.

The number of gun and explosives crimes in 2017 has dropped by more than 81 and 64 percent respectively since 2012, said Li Jingsheng, an official of the ministry's Public Order Administration Bureau, at a news conference in Beijing.

Together with 23 other departments, the ministry launched a campaign on Wednesday to intensify the crackdown on gun and explosives crimes. The campaign will last until the end of 2019.

It will especially target online trading in firearms and parts as around 80 percent of illegal firearm transactions are currently via the internet, Li said. "Some people buy gun parts online and then assemble them. We will also step up control of the materials that can be used to make gun parts."

Besides reporting suspicious activities and transactions online, internet companies also need to step up security measures to prevent people from hacking into the websites to post gun- and explosive-related content, said Zhang Hongye, deputy director of the ministry's Internet Security Bureau.

Preventing people from smuggling firearms from neighboring countries is another focus of the campaign, Li said. Border officers will step up efforts to search for firearms during routine inspections, he added.

The Chinese authorities seized 1.01 million illegal guns and 56.61 million bullets from 2012 to 2017, and the number of gun crimes dropped from 311 in 2012 to 58 in 2017, he added. Individuals are banned from owning firearms in China.

"China is among the countries with the lowest gun and explosives crime rates. However, such crimes are prominent factors that threaten public security," Li said.

Although the number of violent gun crimes, including homicide, robbery and kidnapping, has dropped significantly in recent years, the incidence of illegal gun smuggling and sale has become high, said Dong Xiaogang, an official from the ministry's Criminal Investigation Bureau.

"Driven by profits, some people still choose to manufacture and sell illegal firearms and ammunition. Their behavior has posed severe threats to public security and led to the occurrence of serious cases sometimes," Dong said.

Public security departments around China have launched a series of campaigns targeting gun and explosives crimes in recent years. The ministry will monitor the progress of the latest campaign in areas where such a crime rate is relatively higher, Li said.