Police guard confiscated cocaine weighing 400.5 kilograms seized in a major crackdown on an international drugtrafficking chain controlled by Hong Kong residents. [Photo provided To China Daily]

A major international drug-trafficking chain that police say was controlled by Hong Kong residents has been busted after a crackdown on cross-border drug gangs this month.

A total of 400.5 kilograms of cocaine from South America estimated to be worth more than 334 million yuan ($51.6 million) was seized following the crackdown, according to Deng Jianwei, director of drug enforcement at the Guangdong Department of Public Security.

It was the first time such a large amount of cocaine had been seized in Guangdong in recent years, Deng told a news conference in Shenzhen on Monday. Deng said he believed Guangdong was not the cocaine's final destination.

"This indicates foreign traffickers are using Guangdong, which has advanced transportation networks, as a major transit center to distribute drugs to other nations and regions," Deng said.

Nine suspects, including five Hong Kong residents, were detained following the crackdown.

"Hong Kong and Taiwan residents have been key members of major cross-border drug gangs involved in significant cases busted in Guangdong in recent years," Deng said. "Hong Kong and Taiwan residents control major drug sales channels and major drug customers around the world."

Last year, Guangdong police detained at least 200 Hong Kong residents and 70 from Taiwan after cracking down on major cross-border drug cases, he added.

Deng Guangsheng, deputy director of drug enforcement at Shenzhen Public Security Bureau, said a special task force was set up to investigate the case in late March after local police reported domestic and overseas drug traffickers were bringing cocaine into Guangdong.